Muscle Trainer

K181728 · Shenzhen Kentro Medical Electronics Co., Ltd. · NGX · Oct 17, 2018 · Physical Medicine

Device Facts

• Record ID: K181728
• Device Name: Muscle Trainer
• Applicant: Shenzhen Kentro Medical Electronics Co., Ltd.
• Product Code: NGX · Physical Medicine
• Decision Date: Oct 17, 2018
• Decision: SESE
• Submission Type: Traditional
• Regulation: 21 CFR 890.5850
• Device Class: Class 2
• Attributes: Therapeutic

Intended Use

To be used to stimulate healthy muscles in order to improve and facilitate muscle performance.

Device Story

Muscle Trainer is a powered muscle stimulator for OTC use; delivers electrical pulses to user's skin via electrode patches. Device consists of a host unit and electrode patches; powered by CR2032 button batteries. User selects from 12 intensity levels and 3 operation modes. Device generates biphasic, symmetric, square-wave pulses. Used on abdomen, shoulder, arm, thigh, or calf depending on model. Provides muscle conditioning; benefits include improved muscle performance. Healthcare provider/user interaction involves applying electrodes to skin and adjusting intensity via control buttons. Device includes automatic shut-off and no-load trip features for safety.

Clinical Evidence

Bench testing only. No clinical data provided. Testing included electrical safety (IEC 60601-1, IEC 60601-1-11), electromagnetic compatibility (IEC 60601-1-2), and performance testing (IEC 60601-2-10). Waveform verification performed under load conditions (0.5kΩ, 2kΩ, 10kΩ). Electrode patch current dispersion and shelf-life testing conducted per ASTM F 1980-07.

Technological Characteristics

Powered muscle stimulator; ABS housing; CR2032 (DC3V) battery. Electrode patches use EVA foam, carbon film, conductive hydrogel, and PET. Output: biphasic, symmetric, square-wave pulses. 12 intensity levels; 3 modes. Compliant with IEC 60601-1, IEC 60601-1-2, IEC 60601-1-11, and IEC 60601-2-10. Sterilization not specified; electrodes are cleared components (K171381).

Indications for Use

Indicated for healthy individuals to stimulate muscles to improve and facilitate muscle performance. No specific age or gender restrictions; contraindications not explicitly listed.

Regulatory Classification

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.

Predicate Devices

• GYMFORM® ABS & CORE/VDPGYCSET0042 (K142055)
• HIVOX OTC Electrical Stimulator/SEM44 (K171803)

Submission Summary (Full Text)

{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. To the right of the blue square is the text "U.S. FOOD & DRUG ADMINISTRATION" in blue.

October 17, 2018

Shenzhen Kentro Medical Electronics Co., Ltd % Rain Yip Registered Engineer Feiying Drug & Medical Consulting Technical Service Group Rm. 3005, Area B, Bldg.1, Southward Ruifeng Business Center, Guimiao Road Shenzhen, Cn 518000 Guangdong

Re: K181728

Trade/Device Name: Muscle Trainer Regulation Number: 21 CFR 890.5850 Regulation Name: Powered Muscle Stimulator Regulatory Class: Class II Product Code: NGX Dated: July 14, 2018 Received: July 17, 2018

Dear Rain Yip:

We have reviewed vour 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

{1}------------------------------------------------

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 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/CombinationProducts/GuidanceRegulatoryInformation/ucm597488.htm); 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 http://www.fda.gov/MedicalDevices/Safety/ReportaProblem/default.htm.

For comprehensive regulatory information about mediation-emitting products, including information about labeling regulations, please see Device Advice (https://www.fda.gov/MedicalDevices/DeviceRegulationandGuidance/) and CDRH Learn (http://www.fda.gov/Training/CDRHLearn). 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 (http://www.fda.gov/DICE) for more information or contact DICE by email ([e-mail]) or phone [phone] or 301-796-7100).

Sincerelv.

Vivek J. Pinto -S

for Carlos L. Peña, PhD, MS Director Division of Neurological and Physical Medicine Devices Office of Device Evaluation Center for Devices and Radiological Health

Enclosure

{2}------------------------------------------------

# Indications for Use

510(k) Number (if known) K181728

Device Name Muscle Trainer

Indications for Use (Describe)

To be used to stimulate healthy muscles in order to improve and facilitate muscle performance.

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

Prescription Use (Part 21 CFR 801 Subpart D)

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

#### CONTINUE ON A SEPARATE PAGE IF NEEDED.

This section applies only to requirements of the Paperwork Reduction Act of 1995.

#### *DO NOT SEND YOUR COMPLETED FORM TO THE PRA STAFF EMAIL ADDRESS BELOW.*

The burden time for this collection of information is estimated to average 79 hours per response, including the time to review instructions, search existing data sources, gather and maintain the data needed and complete and review the collection of information. Send comments regarding this burden estimate or any other aspect of this information collection, including suggestions for reducing this burden, to:

> Department of Health and Human Services Food and Drug Administration Office of Chief Information Officer Paperwork Reduction Act (PRA) Staff [e-mail]

"An agency may not conduct or sponsor, and a person is not required to respond to, a collection of information unless it displays a currently valid OMB number."

{3}------------------------------------------------

# 510(k) Summary

## Date: 2018-06-04

#### I. Submitter

SHENZHEN KENTRO MEDICAL ELECTRONICS CO., LTD

No.3, Xihu Industry Zone, Xikeng Village, Henggang Town, Longgang District, Shenzhen City, Guangdong Province, China

Tel.: [phone] Tax: [phone]

Zewu Zhang (Management representative) Tel: [phone] Email: [e-mail]

# II. Device

Type of 510(k): Traditional Common Name: Powered muscle stimulator Trade Name: Muscle Trainer Models: KTR-230 series, KTR-231, KTR-232, KTR-233, KTR-234 Classification Name: Stimulator, Muscle, Powered, For muscle conditioning Review Panel: Physical Medicine Regulatory Class: II Product Code: NGX Regulation Number: 21 CFR 890.5850

# III. Predicate Device

| Applicant | | Predicate Device | | 510(k) Number | Approval Date |
|----------------------------|--------|---------------------------------------------------|--|---------------|---------------|
| Well<br>International Ltd. | Brain | (Primary):<br>GYMFORM®ABS &<br>CORE/VDPGYCSET0042 | | K142055 | May 11, 2015 |
| HIVOX<br>INC. | BIOTEK | HIVOX OTC Electrical<br>Stimulator/SEM44 | | K171803 | Nov.29, 2017 |

# IV. Device Description

Muscle Trainer is a product that adopts modern electronic science and technology to delivers electric pulses generated to the user's skin through the electrodes.

Muscle Trainer is mainly composed of the host and electrode patches, as well as it is powered by CR2023 battery. Of which, the electrode patch is cleared in K171381.

{4}------------------------------------------------

Muscle Trainer includes KTR-230 series (KTR-230B, KTR-230W, KTR-230P), KTR-231, KTR-232, KTR-233 and KTR-234 model. All models have three operation modes and one channel, which can give certain electrical pulse through electrode patches on the skin. Their technical parameters are slightly different, but they share the basically same characteristics:

- Electric pulse combination, 0~12 levels can be adjusted and chosen according to personal preference.
- CR2032 Button batteries (DC3V) power supply, easy to use and safe.

The main differences among them are the followings but not affect its intended use:

- Appearance
- The number of control button: KTR-230 series, KTR-231 and KTR-232 have two buttons to control: KTR-233 and KTR-234 have three buttons to control.
- The number of electrode patch used: KTR-230 series, KTR-233 and KTR-234 are equipped with one electrode patch; KTR-231 is equipped with six electrode patches as well as KTR-232 is equipped with two electrode patches.
- Applied parts: KTR-230 series, KTR-233 and KTR-234 apply to abdomen, shoulder, arm, thigh and calf; KTR-231 applies to abdomen in the place where between ribs and hip bones; KTR-232 applies to waist, shoulder, arm, thigh and calf.

# V. Indications for Use

To be used to stimulate healthy muscles in order to improve and facilitate muscle performance.

# VI. Comparison of Technological Characteristics With the Predicate Devices

The Muscle Trainer is substantially equivalent to the predicated device based on intended use, design, specifications and performance.

The Muscle Trainer does not raise different questions of safety and effectiveness as compared to the predicate devices.

Information for predicate device was obtained from publicly available sources, including the 510(k) Summary and device instruction manual. A technical comparison to the predicate is provided below:

{5}------------------------------------------------

| Comparison<br>Elements | Subject Device | Primary Predicate Device<br>K142055 | Predicate Device 1<br>K171803 | | |
|--------------------------------------------------|-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|------------------------------------------------------------------------------------------------|--------------|
| 510(k) number | K181728 | K142055 | K171803 | / | |
| Trade name | Muscle<br>Trainer/KTR-230series,<br>KTR-231, KTR-232, KTR-233,<br>KTR-234 | GYMFORM®<br>VDPGYCSET0042 | HIVOX OTC Electrical<br>Stimulator/SEM44 | / | |
| Product code | NGX | NGX | NUH<br>NGX | / | |
| Indication<br>for<br>use/Intended use | To be used to stimulate healthy<br>muscles in order to improve and<br>facilitate muscle performance. | GYMFORM®ABS& CORE is<br>intended to stimulate healthy<br>muscles in order to improve or<br>facilitate muscle performance. The<br>ABS& CORE may be considered a<br>technique or method for muscle<br>training. 2-area belt is intended for<br>use on the muscles in abdomen or<br>lower back separately. Mini belt is<br>intended for use on the muscles in<br>arms, legs, thighs or buttocks areas<br>separately | "HIVOX OTC Electrical Stimulator,<br>SEM44 –<br>TENS: The device is designed to be<br>used for temporary relief of pain<br>associated with sore and aching<br>muscles in the shoulder, waist, back,<br>neck, upper extremities (arm), lower<br>extremities (leg), abdomen and<br>bottom due to strain from exercise o<br>normal household work activities.<br>EMS: The device is designed to be<br>used for stimulate healthy muscles in<br>order to improve and facilitate<br>muscle performance" | SE<br>NOTE 4 | |
| Location for use | OTC | OTC | OTC | SE | |
| BASIC UNIT SPECIFICATIOSN | | | | | |
| Power supply | 2032 Button battery (DC3V) | 2 ×1.5V AAA batteries | 4.5V (batteries, 3×1.5V AAA) | SE | |
| Comparison<br>Elements | Subject Device | Primary Predicate Device<br>K142055 | Predicate Device 1<br>K171803 | | |
| | | | | NOTE 1 | |
| Number of output<br>modes | | 3 | 6 | TENS: 15<br>EMS: 35 | SE<br>NOTE 1 |
| | Channel<br>Number | 1 | 2 | 2 | SE<br>NOTE 1 |
| Number<br>of output<br>channels | Synchro<br>nous or<br>Alternat<br>ing? | N/A | Alternating | Synchronous | SE |
| | Method<br>of<br>Channel<br>Isolation | N/A | Press MODE button for 3 seconds | By electrical circuit and software | SE |
| Regulated Current<br>or Voltage? | | Regulated Voltage | Regulated Voltage | Regulated Voltage | SE |
| Software/Firmware<br>/Microprocessor<br>Control? | | Yes | Yes | Yes | SE |
| Automatic overload<br>trip voltage level? | | No | No | Yes | SE |
| Automatic no-load<br>trip? | | Yes | Yes | Yes | SE |
| Automatic shut off | | Yes | Yes | Yes | SE |
| Comparison<br>Elements | Subject Device | Primary Predicate Device<br>K142055 | Predicate Device 1<br>K171803 | | |
| Patient override<br>control? | Yes | Yes | Yes | SE | |
| Indicator<br>Display | On/Off<br>Status? | Yes | Yes | Yes | SE |
| | Low<br>Battery? | Yes | Yes | Yes | SE |
| | Voltage/<br>Current<br>Level? | N/A | Yes | Yes | SE |
| Timer range | | Default 15-minute | Default 10-minute | 5-100 minutes | SE |
| Compliance<br>with<br>voluntary standards | | ■ IEC60601-1-2<br>■ IEC60601-1<br>■ IEC60601-1-11<br>■ IEC60601-2-10 | ■ IEC60601-1-2<br>■ IEC60601-1<br>■ IEC60601-2-10 | ■ IEC60601-1-2<br>■ IEC60601-1<br>■ IEC60601-2-10 | SE |
| Compliance<br>with<br>21CFR 898 | | Yes | Yes | Yes | SE |
| Dimensions<br>(L*W*H) | | (Host)<br>KTR-230 series: φ51×13.5mm<br>KTR-231: φ51×13.5mm<br>KTR-232: φ51×13.5mm<br>KRT-233: 53.4×47.5×11.8mm<br>KTR-234: 49×49×12.6mm | 100mm×68mm×24.5mm | 132mm×63mm×29.5mm (including<br>belt clip) | SE<br>NOTE 2 |
| Weight | | (Host)<br>KTR-230 series: 0.6oz<br>KTR-231: 0.6oz<br>KTR-232: 0.6oz<br>KTR-233: 0.6oz | 50g (Without batteries) | 89g (including belt clip, without<br>batteries)<br>123g (including belt clip and<br>batteries) | SE<br>NOTE 2 |
| Comparison<br>Elements | Subject Device | Primary Predicate Device<br>K142055 | Predicate Device 1<br>K171803 | | |
| | KTR-234: 0.56oz | | | | |
| Housing<br>material<br>and construction | ABS | ABS | ABS | SE | |
| OUTPUT SPECIFICATIOSNS | | | | | |
| Waveform | Mode 1: Pulsed symmetric, biphasic,<br>square wave<br>Mode 2: Pulsed symmetric, biphasic,<br>square wave<br>Mode 3: Pulsed symmetric, biphasic,<br>square wave | Symmetrical, rectangular | Biphasic, square | SE | |
| Maximum<br>output<br>voltage | Mode 1:<br>(±10%)Vp<br>36.5V @500Ω<br>58.5V @2kΩ<br>93 V @10kΩ<br>Mode 2:<br>(±10%)Vp<br>36.5V @500Ω<br>58.5V @2kΩ<br>93 V @10kΩ<br>Mode 3:<br>(±10%)Vp<br>36.5V @500Ω<br>58.5V @2kΩ<br>93 V @10kΩ | (±10%)Vp<br>66V @ 500 Ω<br>69V @ 2k Ω<br>70V @ 10k Ω | (±10%)Vp<br>50V @ 500 Ω<br>60V @ 2k Ω<br>125V @ 10k Ω | SE<br>NOTE 3 | |
| Maximum<br>output | Mode 1:<br>(±10%) Ip | (±10%)Ip<br>132mA @ 500 Ω | (±10%)Ip<br>100mA @ 500 Ω | SE<br>NOTE 3 | |
| Comparison<br>Elements | Subject Device | Primary Predicate Device<br>K142055 | Predicate Device 1<br>K171803 | | |
| current | 73mA @ 500 Ω<br>29.25mA @ 2k Ω<br>9.3mA @ 10k Ω<br><br>Mode 2:<br>(±10%) Ip<br>73mA @ 500 Ω<br>29.25mA @ 2k Ω<br>9.3mA @ 10k Ω<br><br>Mode 3:<br>(±10%) Ip<br>73mA @ 500 Ω<br>29.25mA @ 2k Ω<br>9.3mA @ 10k Ω | 34.5mA @ 2k Ω<br>7mA @ 10k Ω | 45mA @ 2k Ω<br>12.5mA @ 10k Ω | | |
| Net charge (per<br>pulse) | @500Ω<br>Mode 1: 0<br>Mode 2: 0<br>Mode 3: 0 | 19.2μC @ 500 Ω | 0.001μC @ 500 Ω | SE | |
| Maximum phase<br>charge @500Ω | Mode 1: 6.85μC@500 Ω<br>Mode 2: 10.11µC@500 Ω<br>Mode 3: 10.11µC@500 Ω | 16.4µC @ 500 Ω | 0.045μC @ 500 Ω | SE<br>NOTE 3 | |
| Maximum average<br>current @500Ω | Mode 1: 3.6mA@500 Ω<br>Mode 2: 1.1mA@500 Ω<br>Mode 3: 5.4mA@500 Ω…