Predicate Devices

Reference Devices

AI/ML (Artificial Intelligence / Machine Learning)

No
The description focuses on electrical stimulation waveforms and protocols, with no mention of AI or ML. The "IntelliPhase" and "IntelliCycle" names appear to be marketing terms for pre-programmed or automated sequences, not indicative of learning or adaptive algorithms.

Therapeutic

Yes.
The device's stated 'Intended Use / Indications for Use' include several therapeutic applications, such as "Relaxation of muscle spasms," "Prevention or retardation of disuse atrophy," "Increase local blood circulation," and "Immediate post-surgical stimulation of calf muscles to prevent venous thrombosis." These are all conditions that benefit from treatment, indicating its therapeutic nature.

Diagnostic

No

The device description and intended use indicate that the accufit provides electrical stimulation for muscle contraction and re-education, not for diagnosing conditions.

SaMD (Software as a Medical Device)

No

The device description explicitly states that the system console contains hardware components such as a Touch LCD/GUI, electrodes, and a power supply module. It also mentions a key switch and an emergency stop button, which are physical components. The principle of operation involves direct electrical stimulation via electrodes, indicating a hardware-based function.

IVD (In Vitro Diagnostic)

Based on the provided information, the accufit device is not an IVD (In Vitro Diagnostic).

Here's why:

IVD Definition: In Vitro Diagnostics are medical devices used to examine specimens taken from the human body (like blood, urine, or tissue) to provide information about a person's health.
Accufit's Function: The accufit device works by applying electrical stimulation directly to the muscles on the body's surface. It does not analyze any specimens taken from the body.
Intended Use: The intended uses listed are all related to direct muscle stimulation for therapeutic and cosmetic purposes (relaxation, strengthening, circulation, etc.). None of these involve analyzing biological samples.
Device Description: The description clearly states the device generates electrical stimulation to contract muscles using electrodes applied to the skin.

Therefore, the accufit device falls under the category of a physical therapy or muscle stimulation device, not an In Vitro Diagnostic.

PCCP (Predetermined Change Control Plan) Authorized

N/A

Overview

Intended Use / Indications for Use

The accufit is indicated for use for Relaxation of muscle spasms, Prevention or retardation of disuse atrophy, Increase local blood circulation, Muscle re-education, Maintaining or increasing range of motion, Immediate post-surgical stimulation of calf muscles to prevent venous thrombosis, Improvement of abdominal tone, for strengthening of the abdominal muscles, for development of firmer abdomen, and Improvement of muscle tone and firmness, for strengthening muscles in arms, thighs and buttocks areas.

Product codes

IPF, NGX

Device Description

The principle of operation of the accufit device is to provide direct electrical stimulation of muscles which produces muscle contractions in and around the area of the treatment electrodes.

The accufit generates electrical stimulation to contract the muscles to achieve the desired intended use using unique IntelliPhase waveforms and IntelliSTIM electrodes. It offers two unique IntelliPhase waveforms, Biphasic and Interferential (4P), that are designed to optimize muscle re-education and activation for patients. The four IntelliPhase waveform protocols are twist, hold, grip, and tap. Each protocol may be used for 15, 30, or 45 minutes. Not only are there four IntelliPhase protocols, but there is also a fully automated protocol (IntelliCycle) that integrates all the above listed waveforms in a comprehensive, interlaced series. This engages all the targeted muscles in a continuous program to maximize muscle effects with the touch of a button.

accufit is both the proprietary-trade name and generic name. accufit is a supplement to existing treatments and does not replace any traditional treatment or therapy.

The system console is the heart of the accufit and contains the Touch LCD/GUI, electrodes, and power supply module. The main console also includes a key switch used to turn the power on and off, and an emergency stop push button that quickly de-energizes the system in emergency situations. There are 4 casters in the console base that can be used when moving the system.

Mentions image processing

Not Found

Mentions AI, DNN, or ML

Not Found

Input Imaging Modality

Not Found

Anatomical Site

Muscles in arms, thighs, buttocks, and abdomen. Calf muscles.

Indicated Patient Age Range

Not Found

Intended User / Care Setting

Not Found

Description of the training set, sample size, data source, and annotation protocol

Not Found

Description of the test set, sample size, data source, and annotation protocol

Not Found

Summary of Performance Studies (study type, sample size, AUC, MRMC, standalone performance, key results)

A clinical study was performed to assess the effect of the device on the strengthening and appearance of arms. 45 subjects were enrolled in the study and treated with this bioelectric muscle activation (BMA) device. Strength was measured with a dynamometer device at baseline, at the final treatment session, and at the posttreatment 30- and 90-day assessment. The device was tolerated, and most patients saw improvement in muscle strength from the initial to final treatment, as measured by the dynamometer. There were no significant adverse events noted in the duration of the study.

Key Metrics (Sensitivity, Specificity, PPV, NPV, etc.)

Not Found

Predicate Device(s)

K223802

Reference Device(s)

K192039, K092476

Predetermined Change Control Plan (PCCP) - All Relevant Information

Not Found

Regulation Number and Section

§ 890.5850 Powered muscle stimulator.

(a)
Identification. A powered muscle stimulator is an electrically powered device intended for medical purposes that repeatedly contracts muscles by passing electrical currents through electrodes contacting the affected body area.(b)
Classification. Class II (performance standards).

Summary

0

Image /page/0/Picture/0 description: The image contains 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. Underneath the square are the words "U.S. FOOD & DRUG ADMINISTRATION" in blue.

March 21, 2024

Mettler Electronics Corporation Kevin O'Connell VP Global Regulatory Affairs Lutronic Corporation Lutronic Center 219, Sowon-Ro Deogyang-Gu, Goyang-Si 410220 South Korea

Re: K233926

Trade/Device Name: accufit Regulation Number: 21 CFR 890.5850 Regulation Name: Powered Muscle Stimulator Regulatory Class: Class II Product Code: IPF, NGX Dated: March 7, 2024 Received: March 7, 2024

Dear Kevin O'Connell:

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 (the 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 available 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.

1

Additional information about changes that may require a new premarket notification are provided in the FDA guidance documents entitled "Deciding When to Submit a 510(k) for a Change to an Existing Device" (https://www.fda.gov/media/99812/download) and "Deciding When to Submit a 510(k) for a Software Change to an Existing Device" (https://www.fda.gov/media/99785/download).

Your device is also subject to, among other requirements, the Quality System (OS) regulation (21 CFR Part 820), which includes, but is not limited to, 21 CFR 820.30, Design controls; 21 CFR 820.90, Nonconforming product; and 21 CFR 820.100, Corrective and preventive action. Please note that regardless of whether a change requires premarket review, the QS regulation requires device manufacturers to review and approve changes to device design and production (21 CFR 820.30 and 21 CFR 820.70) and document changes and approvals in the device master record (21 CFR 820.181).

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 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 Part 803) for devices or postmarketing safety reporting (21 CFR Part 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 Part 4, Subpart A) for combination products; and, if applicable, the electronic product radiation control provisions (Sections 531-542 of the Act); 21 CFR Parts 1000-1050.

Also, please note the regulation entitled, "Misbranding by reference to premarket notification" (21 CFR 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.

Heather L. Dean -S

Heather Dean, PhD Assistant Director, Acute Injury Devices Team DHT5B: Division of Neuromodulation

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Enclosure

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Indications for Use

510(k) Number (if known) K233926

Device Name accufit

Indications for Use (Describe)

Relaxation of muscle spasms
Prevention or retardation of disuse atrophy
Increase local blood circulation
Muscle re-education
Maintaining or increasing range of motion
Immediate post-surgical stimulation of calf muscles to prevent venous thrombosis
Improvement of abdominal tone, for strengthening of the abdominal muscles, for development of firmer abdomen.
Improvement of muscle tone and firmness, for strengthening muscles in arms, thighs and buttocks areas.

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

Prescription Use (Part 21 CFR 801 Subpart D)

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

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510(k) SUMMARY

K233926

A summary of 510(k) safety and effectiveness information in accordance with the requirements of 21 CFR 807.92.

807.92(a)(1) - Submitter Information
Name	Mettler Electronics Corporation
Address	1333 South Claudina Street
Anaheim, CA USA 92805
Phone number	978-888-1426
Fax number	N/A
Name of contact person	An Le
QS/RA Manager, Mettler Electronics Corporation
1333 South Claudina Street
Anaheim, CA 92805
Date prepared	March 19, 2024
807.92(a)(2) - Name of device
Trade or proprietary name	accufit
Common or usual name	Powered Muscle Stimulator
Classification name	Stimulator, Muscle, Powered, For Muscle Conditioning
Classification panel	Physical Medicine
Regulation	21 CFR 890.5850
Product Code(s)	IPF, NGX
807.92(a)(3) - Legally marketed device(s) to which equivalence is claimed
Mettler Electronics Corporation K223802 (10/06/2023) Predicate
Johari Digital Healthcare Limited K192039 (03/29/2020) Reference
Sport- Elec K092476 (05/07/2010) Reference
807.92(a)(4) - Device description
The principle of operation of the accufit device is to provide direct
electrical stimulation of muscles which produces muscle contractions in
and around the area of the treatment electrodes.

The accufit generates electrical stimulation to contract the muscles to
achieve the desired intended use using unique IntelliPhase waveforms
and IntelliSTIM electrodes. It offers two unique IntelliPhase
waveforms, Biphasic and Interferential (4P), that are designed to
optimize muscle re-education and activation for patients. The four
IntelliPhase waveform protocols are twist, hold, grip, and tap. Each | |
| protocol may be used for 15, 30, or 45 minutes. Not only are there four
IntelliPhase protocols, but there is also a fully automated protocol
(IntelliCycle) that integrates all the above listed waveforms in a
comprehensive, interlaced series. This engages all the targeted muscles
in a continuous program to maximize muscle effects with the touch of a
button. | |
| accufit is both the proprietary-trade name and generic name. accufit is a
supplement to existing treatments and does not replace any traditional
treatment or therapy. | |
| The system console is the heart of the accufit and contains the Touch
LCD/GUI, electrodes, and power supply module. The main console
also includes a key switch used to turn the power on and off, and an
emergency stop push button that quickly de-energizes the system in
emergency situations. There are 4 casters in the console base that can
be used when moving the system. | |
| 807.92(a)(5) Intended use of the device | |
| Indications for use | The accufit is indicated for use for Relaxation of muscle spasms,
Prevention or retardation of disuse atrophy, Increase local blood
circulation, Muscle re-education, Maintaining or increasing range of
motion, Immediate post-surgical stimulation of calf muscles to prevent
venous thrombosis, Improvement of abdominal tone, for strengthening
of the abdominal muscles, for development of firmer abdomen, and
Improvement of muscle tone and firmness, for strengthening muscles in
arms, thighs and buttocks areas. |

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807.92(a)(6) Summary of the technological characteristics of the device compared to the predicate
Model Name	accufit	accufit	Torc Body	Body Control
System "4M"	Notes
510(k) #	Subject device	K223802	K192039	K092476
Manufacturer	Mettler	Mettler	Johari Digital
Healthcare Limited	Sport-Elec S.A
Indications for Use	• Relaxation of muscle
spasms
• Prevention or
retardation of disuse
atrophy
• Increase local blood
circulation
• Muscle re-education
• Maintaining or
increasing range of
motion
• Immediate post-
surgical stimulation of
calf muscles to prevent
venous thrombosis
• Improvement of
abdominal tone, for
strengthening of the
abdominal muscles, for
development of firmer
abdomen.
Improvement of muscle
tone and firmness, for
strengthening muscles in
arms, thighs and
buttocks areas.	• Relaxation of muscle
spasms
• Prevention or
retardation of disuse
atrophy
• Increase local blood
circulation
• Muscle re-education
• Maintaining or
increasing range of
motion
• Immediate post-
surgical stimulation of
calf muscles to
prevent venous
thrombosis	• Improvement of
abdominal tone, for
strengthening of the
abdominal muscles,
for development of
firmer abdomen.
• Strengthening, toning
and firming of
buttocks & thighs.	Improvement of
muscle tone and
firmness, for
strengthening
muscles in arms,
abdomen, thighs and
buttocks areas.	Identical to predicate
plus reference
devices
Classification	890-5850 - IPF, NGX	890-5850 - IPF	890-5850 - NGX	890-5850 - NGX	Identical to
predicate plus
reference devices
Power Source	100-240VAC ,
50/60Hz, 1.0A (Fuse:
250V / 6.3A)	100-240VAC ,
50/60Hz, 1.0A
(Fuse: 250V / 6.3A)	100-240AC,
50/60Hz, 75VA	Battery powered	Identical
Therapeutic
Modality	Electrical muscle
stimulator	Electrical muscle
stimulator	Electrical muscle
stimulator	Electrical muscle
stimulator	Identical
Treatment Output
Mode	Electrode	Electrode	Electrode	Electrode	Identical
Method of Line
Current
Isolation	Double Insulated Wire
Non- Conductive
Enclosure	Double Insulated
Wire Non-
Conductive
Enclosure	(a) AC Power supply
is converted to DC
Power supply
through a medical
grade PSU.
(b) Isolation thru
transformer in
between device and
patient	Not available	Same as predicate
Measured Patient
Leakage:
Normal Condition
(μ Α)	Less than 100μA	Less than 100μA	Less than 100μA	Not available	Identical
Single Fault
Condition (μΑ)	Less than 100μA	Less than 100μA	Less than 300μA	Not available	Similar
Number of Output
Modes	4	4	3	Not available	1 additional mode
Number of Output
Channels	2	2	2	2	Identical
Regulated Current
or Voltage	Current = 100mA
maximum	Current = 100mA
maximum	103.2 mA pp @ 500
Ohm 31.2 mA pp @
2K Ohm 6.6 mA pp
@ 10K Ohm	Not available	Identical when
compared at 500
Ohm
Pulse Intensities	Adjustable, 0-100 mA
peak into 500ohm load
each Electrode channel	Adjustable, 0-100
mA peak into
500ohm load each
Electrode channel	Not available	Not available	Same as predicate
Software/Firmware/
Microprocessor
Control	yes	yes	yes	Not available	Identical
Automatic Over
Current Trip?	yes	yes	yes	Not available	Identical
Automatic No Load
Trip?	yes	yes	no	Not available	Same as predicate
Automatic Shut
Off?	yes	yes	yes	Not available	Identical
User Override
control?	Patient Interrupt (Stop)
Switch	Patient Interrupt
(Stop) Switch	yes	Not available	Identical
Indicator Display:	yes	yes	yes	Not available	Identical
On/ Off Status?	yes	yes	yes	Not available	Identical
Voltage/ Current
Level?	yes	yes	yes	Not available	Identical
Timer range	15, 30, 45 mins	15, 30, 45 mins	1 – 60 Minutes In
step of 1 minute	Not available	Similar
Compliance:
Voluntary
Standards	IEC 60601-1; 60601-
1-2; 60601-2-10, ISO
14971, UL 60601,
CSA C22.2 No 606.1	IEC 60601-1;
60601-1-2; 60601-2-
10, ISO 14971, UL
60601, CSA C22.2
No 606.1	YES IEC 60601-1,
IEC 60601-1-
2,IEC60601-2-10,
and ISO14971	Not available	Similar
Compliance: 21
CFR 898	yes	yes	yes	Not available	Identical
Weight	27 Kg	27 Kg	32.66 Kgs	Not available	Similar
Dimensions (mm)
W x L x H	452 x 582 x 1101	452 x 582 x 1101	444 x 356 x 1016	84x126x30	Similar
Housing, Materials
and Construction	ABS plastic	ABS plastic	ABS Plastic Body	Not available	Identical

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9

| Medical Equipment

Classification	Type BF	Type BF	Not available	Not available	Identical
807.92(b)(1) NON CLINICAL TESTS SUBMITTED
IEC 60101-1, an International Standard on Medical electrical equipment general requirements for safety (FDA Recognition List
Number 19-4); IEC 60601-1-2, an International Standard on Medical electrical equipment, electro- magnetic compatibility (FDA Recognition List
Number 19-8); IEC 60601-1-6, an International Standard on Medical electrical equipment – Part 1-6: General requirements for basic safety and
essential performance – Collateral standard: Usability (FDA Recognition List Number 5-132), IEC 60601-2-10 an International Standard on Medical electrical equipment - Part 2-10: Particular requirements for the basic safety
and essential performance of nerve and muscle stimulators (FDA Recognition List Number 17-16), and IEC TR 60601-4-2 Medical electrical equipment - Part 4-2: Guidance and interpretation - Electromagnetic immunity:
performance of medical electrical equipment and medical electrical systems (FDA Recognition List Number 19-19). IEC 62304 Medical device software - Software life cycle processes (FDA Recognition List Number 13-79) Cytotoxicity per ISO 10993-5:2009 Skin sensitization per ISO 10993-10:2021 Skin Irritation per ISO 10993-23:2021
807.92(b)(2) CLINICAL TESTS SUBMITTED
A clinical study was performed to assess the effect of the device on the strengthening and appearance of arms. 45 subjects were enrolled in the
study and treated with this bioelectric muscle activation (BMA) device. Strength was measured with a dynamometer device at baseline, at the
final treatment session, and at the posttreatment 30- and 90-day assessment. The device was tolerated, and most patients saw improvement in
muscle strength from the initial to final treatment, as measured by the dynamometer. There were no significant adverse events noted in the
duration of the study.

807.92(b)(3) Conclusion

Based on the companison of the technological characteristics, the specifications for the same or a subset of the Tore Body specifications. The options of two sized electrodes allow the users more options in how the same energy is shaped during delivery. The new indication of strengthening arms is supported by clinical testing. Also, the same as the reference device, SPORT-ELEC BODY CONTROL SYSTEM, MODEL 4M. Therefore, we believe that the subject device is substantially equivalent to the predicate devices.