The BTL-899ST is a non-invasive therapeutic device.
BTL-899ST consists of a main unit and applicator(s). The main unit is equipped with a color touch screen that makes the device easy to use. The on-screen information guides the Operator through the entire therapy procedure. The therapeutic parameters are easily set using the touch screen. During therapy, the screen displays information about the remaining therapy time and other therapy parameters. The device is equipped with the Total Stop Button to terminate the device. The Total Stop Button is located on the rear panel of the main unit. The two outputs (applicators) of the device enable hands-free simultaneous treatment by two applicators.

AI/ML Overview

Here's a summary of the acceptance criteria and the study that proves the device meets them, based on the provided text:

1. Table of Acceptance Criteria and Reported Device Performance

Acceptance Criteria (Primary Efficacy Outcome Measure)	Reported Device Performance (Efficacy Results)
Minimum of 80% of subjects at 30-day follow-up evaluation to show mean thighs circumference reduction of ≥ 1 cm relative to the baseline assessment.	Twenty-two of 29 subjects (75.86%) responded to treatment. Forty-seven of the total 58 thighs treated (81.03%) had circumference reduction of ≥ 1 cm at 1-month follow-up relative to the baseline assessment.
Secondary Endpoints:	Reported Device Performance:
Evaluation of the safety of the BTL-899 device for non-invasive lipolysis (breakdown of fat) of the thighs.	One adverse event (panniculitis) was recorded, judged as related to treatment and mild. Overall, the device showed an acceptable safety profile.
Minimum 80% of treated subjects to report satisfaction (level satisfied and higher) with the therapy.	100% of participants were either satisfied (9 subjects) or very satisfied (20 subjects) with the therapy results.

Note on Primary Efficacy: While 75.86% of subjects responded, 81.03% of the treated thighs showed a reduction of at least 1 cm. The acceptance criteria specify "minimum of 80% of subjects...to show mean thighs circumference reduction of >= 1 cm". The provided text could be interpreted as 22 out of 29 subjects responded indicating individual subject success rather than simply thigh success. However, the subsequent sentence clarifying "Forty-seven of the total 58 thighs treated had circumference reduction of <= 1 cm at 1-month follow-up relative to the baseline assessment" uses "<= 1 cm" instead of ">= 1 cm" in its description which is confusing and may be a typo in the provided document. Assuming it should have been ">=", the 81.03% success rate at the thigh level met the criteria. If it truly was "<= 1 cm" (meaning a reduction of 1 cm or less), it would imply failure to meet the >=1 cm criteria if the goal was a larger reduction. I will assume it's a typo in the document and should be >= 1 cm.

2. Sample Size Used for the Test Set and Data Provenance

Sample Size: N=29 subjects completed follow-up for the primary efficacy and safety analysis. N=40 subjects were initially enrolled/treated. 38 subjects completed the 3-month follow-up (likely for safety).
Data Provenance: The document does not explicitly state the country of origin. It is a clinical study. The timeframe for the study's execution (prospective or retrospective) is not explicitly stated, but the description of "enrolled/treated" and "follow-up" strongly indicates a prospective study.

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

This information is not provided in the document. The study measures circumference reduction and patient satisfaction, which do not typically require a panel of experts to establish a "ground truth" in the way, for example, a diagnostic imaging study would. The measurements (circumference reductions) are objective, and satisfaction is self-reported by subjects.

4. Adjudication Method for the Test Set

This information is not provided as the study design focuses on objective measurements and self-reported satisfaction, not a scenario requiring expert adjudication of results.

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

No, an MRMC comparative effectiveness study was not done. This study is a clinical trial evaluating the device's performance in humans, not comparing human reader performance with and without AI assistance. The device itself is a therapeutic device, not an AI diagnostic tool.

6. Standalone (Algorithm Only Without Human-in-the-Loop Performance) Study

This question is not applicable as the device is a physical therapeutic device (electrosurgical cutting and coagulation device and accessories), not an algorithm or AI system for diagnosis. The study evaluated its direct application on subjects.

7. Type of Ground Truth Used

For efficacy: Direct measurements of thigh circumference reduction (objective, quantitative data) and self-reported patient satisfaction (subjective, qualitative data) served as the "ground truth."
For safety: Observation and reporting of adverse events.

8. Sample Size for the Training Set

This information is not applicable as the device is a physical medical device, not an AI algorithm that requires a "training set" in the machine learning sense. The referenced clinical study is a validation study for establishing efficacy and safety in a human population.

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

This information is not applicable for the same reason as above (not an AI algorithm).

Summary

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Image /page/0/Picture/0 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 is a blue square with the letters "FDA" in white. To the right of the blue square is the text "U.S. FOOD & DRUG ADMINISTRATION" in blue.

January 26, 2021

BTL David Chmel Vice President of Operations 362 Elm Street Marlborough, Massachusetts 01752

Re: K202199

Trade/Device Name: BTL-899ST Regulation Number: 21 CFR 878.4400 Regulation Name: Electrosurgical cutting and coagulation device and accessories Regulatory Class: Class II Product Code: GEI Dated: December 15, 2020 Received: December 18, 2020

Dear David Chmel:

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 statutes and regulations administered by other Federal agencies. You must comply with all the Act's

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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 (OS) 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 mediation-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,

Long Chen, Ph.D. Assistant Director DHT4A: Division of General Surgery Devices OHT4: Office of Surgical and Infection Control 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) K202199

Device Name BTL-899ST

Indications for Use (Describe)

BTL-899ST is indicated to be used for:

· Non-invasive lipolysis (breakdown of fat) of the abdomen.
· Reduction in circumference of the abdomen.
· Non-invasive lipolysis (breakdown of fat) of the thighs.
· Reduction in circumference of the thighs .
· BTL-899ST is intended for use with Skin Type I, II and III.

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/0 description: The image shows the logo for BTL Industries. The logo consists of three blue squares nested inside each other, with the letters "BTL" in white inside the innermost square. To the right of the logo is the text "BTL Industries" in a dark gray sans-serif font. The logo is simple and modern, and the colors are clean and professional.

510(k) Summary

General Information

Sponsor:	BTL Industries, Inc.362 Elm StreetMarlborough, MA 01752Tel: +1-866-285-1656Fax: +1-888-499-2502
Applicant:	BTL Industries, Inc.362 Elm StreetMarlborough, MA 01752Tel: +1-866-285-1656Fax: +1-888-499-2502
Contact Person:	David ChmelBTL Industries, Inc.chmel@btlnet.com
Summary Preparation

Device Name

Date:

Trade/Proprietary Name:	BTL-899ST
Primary Classification Name:	Electrosurgical, Cutting & Coagulation Device & Accessories
Classification Regulation:	878.4400, Class II
Classification Product Code:	GEI

26 January 2020

Legally Marketed Predicate Device

The BTL-899ST is a state-of-the-art high-frequency energy device with accessories and is substantially equivalent to the current product that is already cleared for distribution in the USA under the following 510(k) Premarket Notification numbers:

. BTL-899 (K192224)

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Product Description

Image /page/4/Picture/2 description: The image shows the logo for BTL Industries. The logo consists of three blue squares, each containing the letters "BTL". To the right of the squares is the text "BTL Industries" in a gray, sans-serif font. The logo is simple and modern, and the use of blue and gray gives it a professional look.

The BTL-899ST is a non-invasive therapeutic device.

BTL-899ST consists of a main unit and applicator(s). The main unit is equipped with a color touch screen that makes the device easy to use. The on-screen information guides the Operator through the entire therapy procedure. The therapeutic parameters are easily set using the touch screen. During therapy, the screen displays information about the remaining therapy time and other therapy parameters. The device is equipped with the Total Stop Button to terminate the device. The Total Stop Button is located on the rear panel of the main unit. The two outputs (applicators) of the device enable hands-free simultaneous treatment by two applicators.

Indications for Use

BTL-899ST is indicated to be used for:

. Non-invasive lipolysis (breakdown of fat) of the abdomen.
. Reduction in circumference of the abdomen.
Non-invasive lipolysis (breakdown of fat) of the thighs.
. Reduction in circumference of the thighs.
. BTL-899ST is intended for use with Skin Type I, II and III.

Non-clinical Testing (Performance, Bench Testing)

The BTL-899ST device has been thoroughly evaluated for electrical safety. The device has been found to comply with the following applicable medical device safety standards:

IEC 60601-1	Medical electrical equipment – Part 1: General requirements for basic safetyand essential performance
IEC 60601-1-2	Medical electrical equipment – Part 1-2: General requirements for basic safetyand essential performance - Collateral standard: Electromagnetic disturbances– Requirements and tests
IEC 62304	Medical device software - Software life cycle processes
ISO 14971	Medical devices – Application of risk management to medical devices
ISO 10993-1	Biological evaluation of medical devices – Part 1: Evaluation and testing withina risk management process
ISO 10993-5	Biological evaluation of medical devices – Part 5: Tests for in vitro cytotoxicity
ISO 10993-10	Biological evaluation of medical devices - Part 10: Tests for irritation and skinsensitization

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K202199

Clinical Testing

Image /page/5/Picture/2 description: The image shows the logo for BTL Industries. The logo consists of three blue squares nested inside each other, with the letters "BTL" in white inside the innermost square. To the right of the square logo is the text "BTL Industries" in gray. The font used for "Industries" is a sans-serif font with a futuristic look.

A clinical study has been conducted to demonstrate the performance, clinical efficacy and safety of the BTL-899ST device for non-invasive lipolysis and circumference reduction of thighs. The treatment with the BTL-899 device has shown to be both effective and safe for non-invasive lipolysis and circumference reduction of the thighs.

In total, N=40 subjects were enrolled/treated in the study to be treated with BTL-899ST. N=29 subjects received treatment with the device and completed the 1-month follow-up and 38 subjects in total respected the 3- months follow-up and were examined and interviewed for possible adverse events.

All the subjects were female (average age 40.26) with 17 Fitzpatrick Skin Type (FST) II and 9 with FST III, and with 3 subjects having FST IV.

The primary efficacy outcome measure was a minimum of 80% of subjects at 30-day follow-up evaluation to show thighs mean circumference reduction of ≥ 1 cm relative to the baseline assessment.

Twenty-two of the twenty-nine subjects responded to treatment with the subject device. Forty-seven of the total 58 thighs treated had circumference reduction of ≤ 1 cm at 1-month follow-up relative to the baseline assessment.

All the twenty-nine subjects were either satisfied (9) or very satisfied (20) with the treatment results.

The participants also rated the improvement of their thighs at 1-month follow-up, with results leaning towards much improved.

The secondary endpoint was met with 100% of the participants in this satisfied with the therapy results. Furthermore, 90% of the subjects judged that the appearance of their thighs has been improved.

All the subjects found the therapy comfortable. Eight participants (28%) agreed and 21 (72%) strongly agreed with the statement "I found the treatment comfortable".

A pain rating scale ranging from zero (no pain) to 10 (worst possible pain) was used. Ten persons (34%) reported weak pain. Nineteen subjects (66%) reported no pain at all by choosing a score of zero.

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Image /page/6/Picture/1 description: The image shows the logo for BTL Industries. The logo consists of three interconnected blue squares on the left side. To the right of the squares is the text "BTL Industries" in a dark gray sans-serif font. The logo appears to be for a company in the industrial sector.

The below table is a summary of the study design and results:

Study design	Two-arm, open-label, interventional study
Sample size-	29 subjects completed follow-up
Number of treatmentsand follow-up visits	4 treatments and 2 follow-up visits at 30 and 90 days.
Primary endpoints	The primary efficacy outcome measure was a minimum of 80% of subjectsat 30-day follow-up evaluation to show mean thighs circumferencereduction of $\ge$ 1 cm relative to the baseline assessment.
Secondary endpoints	Evaluation of the safety of the BTL-899 device for non-invasive lipolysis(breakdown of fat) of the thighs.Minimum 80% of treated subjects to report satisfaction (level satisfied andhigher) with the therapy.
Efficacy Results	Twenty-two of the 29 subjects responded to treatment with the subjectdevice. Forty-seven of the total 58 thighs treated had circumferencereduction of $\le$ 1 cm at 1-month follow-up relative to the baselineassessment.
Safety results	One adverse event was recorded. A participant in ARM 1 was diagnosedwith panniculitis on the inner side of one of the thighs. The AE was judged asrelated to the treatment and was mild.

In conclusion, treatment with the BTL-899ST device has shown to be both effective and safe for noninvasive lipolysis and circumference reduction of thighs.

Based on the clinical data of above mentioned clinical study, the BTL-899ST device demonstrated acceptable performance and safety profile of the device for non-invasive lipolysis and circumference reduction of thighs. Results further support substantial equivalence of the subject device compared to the predicate device.

Technological Characteristics

The BTL-899ST device has the same intended use and identical technological characteristics and principles of operation to its predicate device. The BTL-899ST device and its predicate are comprised of a system console and applicator(s). The system console consists of the generators, computer, and the touch-screen control panel.

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Image /page/7/Picture/1 description: The image shows the logo for BTL Industries. The logo consists of three blue squares nested inside each other, with the letters "BTL" in white inside the innermost square. To the right of the logo is the text "BTL Industries" in a gray, sans-serif font.

The mechanism of action and technological similarities and differences between the BTL-899ST device and the predicate device are described below in the comparison table. The differences do not raise any new types of safety or effectiveness questions.

Comparison with the Predicate Device

510(k) number	K202199	K192224	Significant Difference
Device name	BTL-899ST	BTL-899
Company name	BTL Industries, Inc.	BTL Industries, Inc.
Product Codeand Regulation	General & Plastic Surgery21 CFR 878.4400GEI - Electrosurgical, Cutting &Coagulation & Accessories	General & Plastic Surgery21 CFR 878.4400GEI - Electrosurgical, Cutting &Coagulation & Accessories	None
Indications for Use	BTL-899ST is indicated to beused for:• Non-invasive lipolysis(breakdown of fat) of theabdomen.• Reduction in circumference ofthe abdomen• Non-invasive lipolysis(breakdown of fat) of thethighs.• Reduction in circumference ofthe thighs.• BTL-899ST is intended for usewith Skin Type I, II and III.	BTL-899 is indicated to be usedfor:• Non-invasive lipolysis(breakdown of fat) of theabdomen.• Reduction in circumference ofthe abdomen• The BTL-899 is intended foruse with Skin Type I to SkinType III.	Notsignificantlydifferent
Basic Technology	The system combines bipolarradiofrequency withelectromagnetic stimulation.	The system combines bipolarradiofrequency withelectromagnetic stimulation.	None
Clinical Use	Prescription use	Prescription use	None
ElectricalProtection	Class II, BF	Class II, BF	None
User Interface	Touch screen	Touch screen	None
FirmwareControlled	Yes	Yes	None
Number of outputschannels	2	2	None
RF Type	bipolar	bipolar	None
Max. RF Power	60 W (2x30 W)	60 W (2x30 W)	None
RF Frequency	27.12 Mhz	27.12 Mhz	None
Number of Magneticcoils in theApplicator	1	1	None
Magnetic FieldIntensity (on the coilsurface)	0.5 to 1.8 T	0.5 to 1.8 T	None
Pulse RepetitionRate - supported bythe device	1 — 150 Hz	1 – 150 Hz	None
Pulse Duration	280 µs ± 20% µs	280 µs ± 20% µs	None
Waveform	Biphasic	Biphasic	None
Shape	Sinusoidal	Sinusoidal	None
TemperatureSensor	Yes	Yes	None
Selection ofparameters(Intensity, Time)	Yes	Yes	None
Application	Hands-free, applicator fixed byfixation belt	Hands-free, applicator fixed byfixation belt	None
Therapy Time	Up to 30 min	Up to 30 min	None
Energy Source	100 - 240 V AC, 50-60 Hz	100 - 240 V AC, 50-60 Hz	None
System	23 x 39 x 29 in	23 x 39 x 29 in	None
Dimensions(W×H×D)	(592 x 985 x 730 mm)	(592 x 985 x 730 mm)
System Weight	85 kg	85 kg	None
Operating AmbientTemperature	+10°C to +30°C	+10°C to +30°C	None
Operating RelativeHumidity	30% to 75%	30% to 75%	None
EnvironmentalSpecifications	For indoor use only	For indoor use only	None

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Image /page/8/Picture/1 description: The image shows the logo for BTL Industries. The logo consists of three nested blue squares on the left side of the image. To the right of the squares is the text "BTL Industries" in a gray sans-serif font.

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Image /page/9/Picture/1 description: The image shows the logo for BTL Industries. The logo consists of a blue geometric design on the left and the text "BTL Industries" on the right. The geometric design is made up of three squares, each nested inside the other, with the letters "BTL" inside the innermost square.

Substantial Equivalence

The BTL-899ST device has expanded indications for use to include the thighs area.

There are no technological modifications done to the device and its applicator compared to the predicate device.

The Sponsor of this 510(k) submission has conducted a clinical study and based on the positive results achieved in the study the new indications have been added. Additionally, the safety of the device has been evaluated in the study and no new risks have been identified.

Therefore this difference does not raise any new questions of safety or effectiveness.

Conclusion

Based upon the intended use and the known technical and clinical data provided in this pre-market notification, the BTL-899ST device has been shown to be substantially equivalent to the currently marketed predicate device.

Regulation Number and Section

§ 878.4400 Electrosurgical cutting and coagulation device and accessories.

(a)
Identification. An electrosurgical cutting and coagulation device and accessories is a device intended to remove tissue and control bleeding by use of high-frequency electrical current.(b)
Classification. Class II.