Alignment System Cranial is intended to support the surgeon to plan and to achieve a trajectory with surgical instruments during cranial stereotactic procedures.

The indications for use are biopsy of intracranial lesions and placement of stereoelectroencephalography (SEGG) electrodes.

Device Description

The subject device Alignment System Cranial is an image guided surgery system intended to support the surgeon to plan and to achieve a trajectory with surgical instruments during cranial stereotactic procedures using optical tracking technology.

For this purpose, the Alignment System Cranial consists of a combination of hardware and software. The Alignment Software Cranial with its sw components is installed on an Image Guided Surgery (IGS) platform (Curve, Curve Navigation 17700, Kick 2 Navigation Station or Buzz Navigation) consisting of a computer unit, a touch display and an infrared tracking camera. During surgery, the subject device tracks the position of instruments in relation to the patient anatomy and identifies this position on pre- or intraoperative images. The position of the surgical instruments is continuously updated on these images by optical tracking. This position information is used by the Alignment Software Cranial to align either passive or active positioning devices to a planned trajectory for subsequent surgical steps.

The Alignment System Cranial has different configurations of hardware devices depending on which positioning device is used and which indication is performed. The Alignment Software Cranial 2.0 supports the active positioning devices Surgical Base System 1.4 and Cirq Arm System 2.0 (+ Cirq Robotic Alignment Module + Cirq Robotic Disposable Kinematic Unit) as well as the passive positioning device Varioquide. Both types of positioning devices consist of articulated arms with different joints where additional devices and surgical instruments can be attached to for further robotic or manual alignment respectively to a defined trajectory.

In addition, the subject device offers a set of indication specific instruments to support biopsy and sEEG procedures. This instrumentation consists of instrument holders, tracking arrays, guide tubes, reduction tube, bone anchors, drill bits and depth stops. None of the instruments is delivered sterile. All patient contacting materials consist of different alloys of stainless steel.

With this submission, an already existing feature is now performed introducing a new algorithm using artificial intelligence and machine (AI/ML). This ML based functionality is used as an aid in the registration step (in surface matching) by allowing a pre-registration based on guide points which are delivered by this algorithm. This pre-registration step is not mandatory. The AI/ML algorithm is a Convolutional Network (CNN) developed using a Supervised Learning approach. The algorithm was developed using a controlled internal process that defines activities from the inspection of input data to the training and verification of the training process begins with the model observing, learning, and optimizing its parameters based on the training pool data. The model's prediction and performance are then evaluated against the test pool. The test pool data is set aside at the beginning of the project. This is a static algorithm (locked).

The Alignment Software Cranial has the following accessories:

. Automatic Registration providing an automatic registration for subsequent use.
. Automatic Registration iMRI providing an automatic image registration for intraoperatively acquired MR images.

AI/ML Overview

Here's a breakdown of the acceptance criteria and study information based on the provided text:

1. Table of Acceptance Criteria and Reported Device Performance

Acceptance Criteria	Reported Device Performance
Mean Positional Error (instrument's tip) ≤ 2 mm	Mean Positional Error (instrument's tip) ≤ 2 mm (fulfilled)
Mean Angular Error (instrument's axis) ≤ 2°	Mean Angular Error (instrument's axis) ≤ 2° (fulfilled)
Equivalent performance for landmark detection (AI/ML vs. conventional) to third predicate device	Achieved. Testing demonstrated no concerns regarding safety and effectiveness and equivalent performance.
Software Verification & Validation (Major concern level)	Conducted, documentation provided, product specifications, risk analysis/incremental test strategies included.
Usability according to IEC 62366-1	Summative usability carried out in a simulated clinical environment. Final designs proven safe and effective.
Electrical safety according to IEC 60601-1	Achieved
RFID according to AIM 7351731	Achieved
EMC according to IEC 60601-1-2	Achieved
Biocompatibility of instruments	Assessed, considering materials, manufacturing, test data, and history of safety/effectiveness.
Cleaning and disinfection evaluation/reprocessing validation for instruments	Conducted
Mechanical properties of instruments	Performed life cycle simulations and verification of clearance fits, material fatigue, functionality.
Stability performance testing for drill bits	Performed in selected worst-case situations to ensure load resistance.

2. Sample Sizes Used for Test Set and Data Provenance

The document does not explicitly state the numerical sample size for the test set used for the AI/ML algorithm's performance evaluation or for the general system accuracy testing. However, it indicates:

AI/ML Test Set: "The test pool data is set aside at the beginning of the project. This is a static algorithm (locked)." No further details on provenance or numerical size are provided.
System Accuracy Testing: "evaluated considering a realistic clinical setup and representative worst case scenarios." No specific number of cases or data provenance (e.g., country of origin, retrospective/prospective) is mentioned.

3. Number of Experts Used to Establish Ground Truth for the Test Set and Qualifications

The document does not specify the number or qualifications of experts used to establish ground truth for the test set.

4. Adjudication Method for the Test Set

The document does not specify an adjudication method for the test set.

5. Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study

No mention of an MRMC comparative effectiveness study or human reader improvement with AI assistance is provided. The AI/ML component is described as an "aid in the registration step" by providing "pre-registration based on guide points."

6. Standalone (Algorithm Only) Performance Study

Yes, a standalone performance evaluation of the AI/ML algorithm was done. It focused on comparing its landmark detection capabilities to the conventional method: "For the landmark detection feature in the pre-registration step now implemented using AI/ML, performance testing comparing conventional to machine learning based landmark detection was performed showing equivalent performance as in the third predicate device."

7. Type of Ground Truth Used

The document does not explicitly state the type of ground truth (e.g., expert consensus, pathology, outcomes data) used for the AI/ML algorithm's test set or the system accuracy measurements. For the AI/ML, it implies that the ground truth for landmark detection was established against which the algorithm's performance was compared to the predicate's conventional method.

8. Sample Size for the Training Set

The document states: "The algorithm was developed using a controlled internal process that defines activities from the inspection of input data to the training and verification of the training process begins with the model observing, learning, and optimizing its parameters based on the training pool data." However, it does not provide the numerical sample size for the training set.

9. How the Ground Truth for the Training Set Was Established

The document states that the AI/ML algorithm is a "Convolutional Network (CNN) developed using a Supervised Learning approach." This implies that the training data was labeled with the correct ground truth for the landmarks. However, it does not explicitly describe how this ground truth was established (e.g., by experts, manually annotated, etc.).

Summary

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September 9, 2023

Image /page/0/Picture/1 description: The image shows the logo of the U.S. Food and Drug Administration (FDA). On the left is the Department of Health & Human Services logo. To the right of that is the FDA logo, which consists of a blue square with the letters "FDA" in white, followed by the words "U.S. FOOD & DRUG" in blue, and then the word "ADMINISTRATION" in a smaller font size below that.

Brainlab AG Esther Moreno Garcia QM Consultant Olof-Palme-Str.9 Munich, 81829 Germany

Re: K223864

Trade/Device Name: Alignment System Cranial. Alignment Software Cranial. Cirq Alignment Software Cranial Biopsy, Cirq Alignment Software Cranial sEEG, Varioguide Alignment Software Cranial Regulation Number: 21 CFR 882.4560 Regulation Name: Stereotaxic Instrument Regulatory Class: Class II Product Code: HAW Dated: August 10, 2023 Received: August 10, 2023

Dear Esther Moreno Garcia:

We have reviewed your Section 510(k) premarket notification of intent to market the device referenced above and have determined the device is substantially equivalent (for the indications for use stated in the enclosure) to legally marketed predicate devices marketed in interstate commerce prior to May 28, 1976, the enactment date of the Medical Device Amendments, or to devices that have been reclassified in accordance with the provisions of the Federal Food, Drug, and Cosmetic Act (Act) that do not require approval of a premarket approval application (PMA). You may, therefore, market the device, subject to the general controls provisions of the Act. Although this letter refers to your product as a device, please be aware that some cleared products may instead be combination products. The 510(k) Premarket Notification Database located at https://www.accessdata.fda.gov/scripts/cdrh/cfdocs/cfpmn/pmn.cfm identifies combination product submissions. The general controls provisions of the Act include requirements for annual registration, listing of devices, good manufacturing practice, labeling, and prohibitions against misbranding and adulteration. Please note: CDRH does not evaluate information related to contract liability warranties. We remind you, however, that device labeling must be truthful and not misleading.

If your device is classified (see above) into either class II (Special Controls) or class III (PMA), it may be subject to additional controls. Existing major regulations affecting your device can be found in the Code of Federal Regulations, Title 21, Parts 800 to 898. In addition, FDA may publish further announcements concerning your device in the Federal Register.

Please be advised that FDA's issuance of a substantial equivalence determination does not mean that FDA has made a determination that your device complies with other requirements of the Act or any Federal

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statutes and regulations administered by other Federal agencies. You must comply with all the Act's requirements, including, but not limited to: registration and listing (21 CFR Part 807); labeling (21 CFR Part 801); medical device reporting of medical device-related adverse events) (21 CFR 803) for devices or postmarketing safety reporting (21 CFR 4, Subpart B) for combination products (see https://www.fda.gov/combination-products/guidance-regulatory-information/postmarketing-safety-reportingcombination-products); good manufacturing practice requirements as set forth in the quality systems (QS) regulation (21 CFR Part 820) for devices or current good manufacturing practices (21 CFR 4, Subpart A) for combination products; and, if applicable, the electronic product radiation control provisions (Sections 531-542 of the Act); 21 CFR 1000-1050.

Also, please note the regulation entitled, "Misbranding by reference to premarket notification" (21 CFR Part 807.97). For questions regarding the reporting of adverse events under the MDR regulation (21 CFR Part 803), please go to https://www.fda.gov/medical-device-safety/medical-device-reportingmdr-how-report-medical-device-problems.

For comprehensive regulatory information about medical devices and radiation-emitting products, including information about labeling regulations, please see Device Advice (https://www.fda.gov/medicaldevices/device-advice-comprehensive-regulatory-assistance) and CDRH Learn (https://www.fda.gov/training-and-continuing-education/cdrh-learn). Additionally, you may contact the Division of Industry and Consumer Education (DICE) to ask a question about a specific regulatory topic. See the DICE website (https://www.fda.gov/medical-device-advice-comprehensive-regulatoryassistance/contact-us-division-industry-and-consumer-education-dice) for more information or contact DICE by email (DICE@fda.hhs.gov) or phone (1-800-638-2041 or 301-796-7100).

Sincerely,

Image /page/1/Picture/5 description: The image shows the name "Adam D. Pierce -S" in large, bold font on the left side of the image. On the right side of the image, it says "Digitally signed by Adam D. Pierce -S" followed by the date "2023.09.09" and the time "09:08:17-04'00'". The text on the right side of the image is smaller than the text on the left side of the image. The image appears to be a digital signature.

Adam D. Pierce, Ph.D. Assistant Director DHT5A: Division of Neurosurgical, Neurointerventional and Neurodiagnostic Devices OHT5: Office of Neurological and Physical Medicine Devices Office of Product Evaluation and Quality Center for Devices and Radiological Health

Enclosure

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Indications for Use

510(k) Number (if known) K223864

Device Name

Alignment System Cranial; Alignment Software Cranial;

Cirq Alignment Software Cranial Biopsy; Cirg Alignment Software Cranial sEEG;

Varioguide Alignment Software Cranial

Indications for Use (Describe)

Alignment System Cranial is intended to support the surgeon to plan and to achieve a trajectory with surgical instruments during cranial stereotactic procedures.

The indications for use are biopsy of intracranial lesions and placement of stereoelectroencephalography (SEGG) electrodes.

Type of Use (Select one or both, as applicable)
-------------------------------------------------	--

X Prescription Use (Part 21 CFR 801 Subpart D)

| | Over-The-Counter Use (21 CFR 801 Subpart C)

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Image /page/3/Picture/1 description: The image shows the Brainlab logo. The logo consists of a stylized pink symbol on the left, resembling a brain or neural network. To the right of the symbol is the word "BRAINLAB" in bold, pink capital letters. The overall design is clean and modern.

510(k) Summary

August 10, 2023

General Information
Manufacturer	Brainlab AG; Olof-Palme-Str.9, 81829, Munich, Germany
Establishment Registration	8043933
Trade Name	Alignment System CranialAlignment Software CranialCirq Alignment Software Cranial BiopsyCirq Alignment Software Cranial sEEGVarioguide Alignment Software Cranial
Classification Name	Neurological Stereotaxic Instrument
Product Code	HAW
Regulation Number	882.4560
Regulatory Class	Class II
Panel	Neurology
Predicate Device(s)	Primary Predicate: K191597 Stealth Autoguide SystemSecondary Predicate: K210989 Cirq Robotic Alignment SystemThird Predicate: K192703 Cranial Image Guided Surgery System
Contact Information
Primary Contact	Alternate Contact
Esther Moreno Garcia	Chiara Cunico
QM Consultant - Regulatory Affairs	Phone: +49 89 99 15 68 0
Phone: +49 89 99 15 68 0	Fax: +49 89 99 15 68 5033
Email: regulatory.affairs@brainlab.com	Email: chiara.cunico@brainlab.com

1. Indication for Use

Alignment System Cranial is intended to support the surgeon to plan and to achieve a trajectory with surgical instruments during cranial stereotactic procedures.

The indications for use are biopsy of intracranial lesions and placement of stereoelectroencephalography (SEEG) electrodes.

Device Description 2.

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Image /page/4/Picture/1 description: The image shows the Brainlab logo. The logo consists of a stylized pink symbol on the left, resembling a medical symbol or a stylized brain. To the right of the symbol is the word "BRAINLAB" in large, pink, sans-serif letters. The logo is simple and modern, with a focus on the company name.

The Alignment Software Cranial has the following accessories:

. Automatic Registration providing an automatic registration for subsequent use.
. Automatic Registration iMRI providing an automatic image registration for intraoperatively acquired MR images.

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Image /page/5/Picture/1 description: The image shows the Brainlab logo. The logo consists of a stylized brain icon on the left and the word "BRAINLAB" in capital letters on the right. The color of the logo is pink.

3. Substantial Equivalence

COMPARISON OF TECHNOLOGICAL CHARACTERISTICS WITH THE PREDICATE DEVICE

Characteristic	Primary PredicateK191597	Secondary PredicateK210989	Third PredicateK192703	Subject device
Indications foruse	The Stealth Autoguide Systemis a positioning and guidancesystem intended for thespatial positioning andorientation of instrumentholders or tool guides to beused by neurosurgeons toguide standard neurosurgicalinstruments, based on a pre-operative plan and feedbackfrom an image-guidednavigation system with three-dimensional imagingsoftware.The Stealth Autoguide Systemis a remotely-operatedpositioning and guidancesystem, indicated for anyneurological condition inwhich the use of stereotacticsurgery may be appropriate(for example, stereotacticbiopsy, stereotactic EEG, lasertissue ablation, etc.).	The Cirq Robotic AlignmentModule is an intraoperativerobotic positioning systemand an accessory tocompatible Brainlab IGSCranial software applications.Using spatial informationfrom an image guidednavigation system, the CirqRobotic Alignment Moduleenables the surgeon to alignand hold surgical instrumentsaccording to pre-plannedtrajectories.The Cirq Robotic AlignmentModule is indicated forstereotactic biopsies ofintracranial lesions	The Cranial IGS System, whenused with a compatiblenavigation platform andcompatible instrumentaccessories, is intended as animage-guided planning andnavigation system to enablenavigated surgery. It linksinstruments to a virtualcomputer image space onpatient image data that isbeing processed by thenavigation platform.The system is indicated forany medical condition inwhich a reference to a rigidanatomical structure can beidentified relative to images(CT, CTA, X-Ray, MR, MRA andultrasound) of the anatomy,including among others:Cranial biopsies	Alignment System Cranial isintended to support thesurgeon to plan and toachieve a trajectory withsurgical instruments duringcranial stereotacticprocedures.The medical indications foruse are biopsy of intracraniallesions and placement ofstereo-electroencephalography(SEEG) electrodes.
Localizationtechnique	Optical markers on toolholder	Infrared tracking camera isrecognizing infrared passivemarkers	Infrared tracking camera isrecognizing infrared passivemarkers	Same
		Instrument tracking inrelation to the patientsanatomy.	Instrument tracking inrelation to the patientsanatomy.


System accuracy	Under representative worstcase configuration: Meannavigation accuracy of ±2 mmand angular axis displacementof ±2°	Under representative worstcase configuration: Meannavigation accuracy of ±2 mmand angular axis displacementof ±2°	Under representative worstcase configuration: Meannavigation accuracy of ±2 mmand angular axis displacementof ±2°	Same
Operatingprinciple	Preoperative images(StealthStation)Surgical planning(StealthStation)Patient registrationGuidance of instrumentsTrajectory alignment	Preoperative imagesSurgical planningPatient registrationGuidance of instrumentsTrajectory alignment withCirq Arm System plus CirqRobotic Alignment Module	Preoperative imagesSurgical planningPatient registrationGuidance of instrumentsTrajectory alignment withVarioGuide	SameSubject device supportsalignment with bothVarioGuide or with Cirq ArmSystem plus Cirq RoboticAlignment Module
Planningsoftware	Compatible with:S8 Cranial v1.1Synergy Cranial v.3.1	Compatible with:Cranial 3.1Trajectory 2.5	Compatible with:Cranial 3.1Trajectory 2.5	SameIn addition, Intra-optrajectory planning featureadded to Alignment SoftwareCranial
AlignmentInstrumentation	Navigated Trajectory GuideTool Holders (Drill Guides,Reducing Tubes)Height GuidesTapping Tube	Cirq Arm System:Instrument Holder Cranial +Tracking Array Cranial(Navigation and holding)Cranial Drill Bit + Depth Stop(Safe drilling)Biopsy minimally invasive:Guide Tube + Bone Anchor(Holding and guiding of drill)	VarioGuide:Biopsy with burr hole:Compatible disc set (Biopsyneedle guidance)	SimilarAlignment instrumentation isgenerally used in all deviceswith a combination ofholders, guides and tubes.Instrumentation has beenextended to support newsEEG indication.
Instrumentfixation	Special tool holders fordifferent applicationsmounted to the StealthAutoGuide	Cirq Robotic DisposableKinematic Unit to whichinstrument holder is attached	Disc sets are mechanicallyconnected to the VarioGuideassembly depending onguiding diameter	Mechanical connection isused in all devices forinstrument fixation. Identicalto predicate 2 and 3.

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Image /page/6/Picture/1 description: The image shows the Brainlab logo. The logo consists of a stylized pink symbol on the left and the word "BRAINLAB" in pink capital letters on the right. The symbol appears to be a stylized representation of the brain.

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Image /page/7/Picture/1 description: The image features the Brainlab logo, which is rendered in a vibrant pink color. To the left of the word "BRAINLAB" is a stylized graphic, also in pink, that appears to be a representation of the brain. The text "BRAINLAB" is written in a bold, sans-serif font, making it easily readable and prominent within the logo.

Alignmentprocess	Fine alignment roboticallyperformed by Autoguide	Rough alignment:Manual positioning of CirqArm System with Autopilotfeature (Alignment Software)close to final positionFine alignment:Robotic movement of CirqRobotic Alignment Module	Rough and fine alignment bymanual positioning ofVarioGuide along plannedtrajectory with Autopilotfeature (Cranial Navigation)	Similar alignment process asPredicate 1 and identical toPredicates 2 and 3.
PatientRegistration	Optical Registration Device(via StealthStation)	Optical registration fromCranial 3.1Methods: Surface matching,landmark registrationSurface matching: No pre-registration available.	Optical registration(Registration 3.5)Methods: Surface matching,landmark registration.Surface matching: Detectionof anatomical landmarks inpre-registration based on anatlas of the human anatomy.	Optical registration(Registration 3.6). Sameregistration methods as inBrainlab predicates.Compared to Predicate 3,overall functionality is thesame, but landmarks (usedfor pre-registration) aredelivered by an Al/ML basedmethod.Testing demonstrated thereare no concerns regardingsafety and effectiveness.
IGS Platforms	StealthStation surgicalnavigation platformconsisting of computer, touchmonitor and stereotacticcamera.	Curve, Kick and BuzzNavigation models are used,consisting of computer, touchmonitor and IR camera.	Curve, Kick and BuzzNavigation models are used,consisting of computer, touchmonitor and IR camera.	Similar to predicates.Modified platforms (Kick 2Navigation Station and BuzzNavigation) and new platformmodel (Curve Navigation17700) but with overall samecomponents and operatingprinciple.

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Image /page/8/Picture/0 description: The image shows the Brainlab company logo. The logo consists of a stylized caduceus symbol on the left, followed by the word "BRAINLAB" in all capital letters. The color of the logo is a bright pink.

4. Performance Data

The following testing was conducted on the Subject Device to establish substantial equivalence with the predicate devices:

Software Verification and Validation Testing

Software verification and validation testing were conducted and documentation was provided as recommended by FDA's Guidance for Industry and FDA Staff, "Guidance for the Content of Premarket Submissions for Software Contained in Medical Devices." This included product specifications, risk analysis or incremental test strategies. The software for this device was considered as a "major" level of concern.

For the landmark detection feature in the pre-registration step now implemented using AI/ML, performance testing comparing conventional to machine learning based landmark detection was performed showing equivalent performance as in the third predicate device.

Usability Evaluation

Summative usability was carried out according to the standard IEC 62366-1 "Medical devices – Part 1: Application of usability engineering to medical devices" in a simulated clinical environment to validate the new use scenarios: Varioguide for biopsy and Cirq for sEEG workflows. This covered aspects such as the guidance provided by the updated Alignment Software Cranial, the handling of instruments or the assembly of the positioning devices with overall focus on new or changed features. The final designs were proven safe and effective for use in the defined use scenarios.

System accuracy testing

The positional and angular navigation accuracy for biopsy and sEG procedures of the Subject Device including the software, the platforms, the positioning devices and the instruments was evaluated considering a realistic clinical setup and representative worst case scenarios. The results show the following acceptance criteria are fulfilled:

. Mean Positional Error of the placed instrument's tip ≤ 2 mm
. Mean Angular Error of the placed instrument's axis ≤ 2°

Therefore, the Subject Device achieves the same accuracy performance as the three predicate devices considered.

Electrical safety and electromagnetic compatibility (EMC)

Compliance to electrical safety, RFID and EMC was evaluated on the Subject device according to the standards: IEC 60601-1, AIM 7351731 and IEC 60601-1-2. The tests have shown that the subject device performs as intended.

Instruments

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Image /page/9/Picture/1 description: The image shows the Brainlab logo. The logo consists of a stylized pink symbol on the left, resembling a brain with interconnected pathways. To the right of the symbol, the word "BRAINLAB" is written in bold, pink capital letters.

Instruments verification included:

. Biocompatibility assessment considering the materials used in the devices, manufacturing, processing, biological and chemical test data, and the history of safety and effectiveness of the device materials in contact with the human body.
Cleaning and disinfection evaluation/reprocessing validation.
. Mechanical properties of instruments by performing life cycle simulations and verification of clearance fits, material fatigue, functionality, etc.
. Stability performance testing was performed in selected worst case situations for the drill bits to ensure they can withstand the loads they might be exposed to during use.

No clinical testing was needed for the Subject Device since optical tracking technology in the scope of image guided surgery for the included indications for use is well established in the market.

5. Conclusion

The comparison of the Subject Device with the predicate devices shows that the Alignment System Cranial has similar functionality, intended use and technological characteristics as the predicate devices. Based on the comparison to the predicates and the performance testing conducted, the Subject Device is considered substantially equivalent to the predicate devices.

Regulation Number and Section

§ 882.4560 Stereotaxic instrument.

(a)
Identification. A stereotaxic instrument is a device consisting of a rigid frame with a calibrated guide mechanism for precisely positioning probes or other devices within a patient's brain, spinal cord, or other part of the nervous system.(b)
Classification. Class II (performance standards).