Portable Electro-Stimulation Therapy Device

K182108 · Guangzhou Longest Science & Technology Co., Ltd. · NUH · Apr 26, 2019 · Neurology

Device Facts

• Record ID: K182108
• Device Name: Portable Electro-Stimulation Therapy Device
• Applicant: Guangzhou Longest Science & Technology Co., Ltd.
• Product Code: NUH · Neurology
• Decision Date: Apr 26, 2019
• Decision: SESE
• Submission Type: Traditional
• Regulation: 21 CFR 882.5890
• Device Class: Class 2
• Attributes: Therapeutic

Indications for Use

Portable Electro-Stimulation Therapy Device, model LGT-235 is indicated for the Symptomatic relief of chronic intractable pain, Post-traumatic pain and Post-surgical pain of the arms and legs.

Device Story

Portable Electro-Stimulation Therapy Device (LGT-235) is a handheld TENS and Microcurrent (MCR) stimulator for home use. System comprises a main unit, electrodes (knee brace or self-adhesive), and 'MStim Arth' mobile app. Device delivers electrical impulses to sensory nerves via skin electrodes to modify pain perception; does not cure underlying conditions. User operates device via app to select pre-programmed output modes and treatment time, or via main unit to adjust intensity and power. Output affects sensory nerves responsible for pain signal transmission. Benefits include symptomatic pain relief for chronic, post-traumatic, or post-surgical conditions in arms and legs.

Clinical Evidence

Bench testing only. No clinical data provided. Verification and validation testing included electrical safety, mechanical testing, software verification, and biocompatibility (ISO 10993-5/10). Compliance with IEC 60601-1, 60601-1-2, 60601-1-11, and 60601-2-10 standards confirmed.

Technological Characteristics

Handheld TENS/MCR stimulator; 3.7V rechargeable lithium battery. Electrodes: OK cloth/SBR/dacron knee brace with silver/nylon conductive fabric or conductive hydrogel self-adhesive pads. Symmetrical biphasic waveform. Connectivity: Bluetooth/mobile app for control. Standards: ISO 10993, ANSI/AAMI ES60601-1, IEC 60601-1-2, IEC 60601-2-10, IEC 60601-1-11.

Indications for Use

Indicated for adults experiencing chronic intractable pain, post-traumatic pain, or post-surgical pain in the arms and legs.

Regulatory Classification

Identification

A transcutaneous electrical nerve stimulator for pain relief is a device used to apply an electrical current to electrodes on a patient's skin to treat pain.

Predicate Devices

• Sonicator Plus 920, Model ME 920 (K111482)

Submission Summary (Full Text)

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April 26, 2018

Guangzhou Longest Science & Technology Co., Ltd. % You Yijie Manager Oimmig Medical Consulting Service Co., Ltd RM.1711, Building K, NO.101 Science Ave International Creative Valley Guangzhou, 510663 Cn

Re: K182108

Trade/Device Name: Portable Electro-Stimulation Therapy Device Regulation Number: 21 CFR 882.5890 Regulation Name: Transcutaneous Electrical Nerve Stimulator For Pain Relief Regulatory Class: Class II Product Code: GZJ Dated: March 29, 2019 Received: March 29, 2019

Dear You Yijie:

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/CombinationProducts/GuidanceRegulatoryInformation/ucm597488.html; 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 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).

Sincerely,

# Pamela D. Scott -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

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## Indications for Use

510(k) Number (if known) K182108

Device Name Portable Electro-Stimulation Therapy Device

#### Indications for Use (Describe)

Portable Electro-Stimulation Therapy Device, model LGT-235 is indicated for the Symptomatic relief of chronic intractable pain, Post-traumatic pain and Post-surgical pain of the arms and legs.

| Type of Use (Select one or both, as applicable) | |
|---------------------------------------------------------------------------------------|--------------------------------------------------------------------------------------|
| <div> <span> </span> <span>Prescription Use (Part 21 CFR 801 Subpart D)</span> </div> | <div> <span> </span> <span>Over-The-Counter Use (21 CFR 801 Subpart C)</span> </div> |

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# 510(K) Summary

Date: April 24, 2019

#### 1. Submitter's Information

#### Establishment Registration Information

Name: Guangzhou Longest Science & Technology Co., Ltd. Address: 5&6f, Building B4, No.11, Kaiyuan Avenue Science City, Hi-Tech Industrial Zone Guangzhou, Guangdong CHINA

#### Contact Person of applicant

Name: Xiaobinq Luo Address: 5&6f, Building B4, No.11, Kaiyuan Avenue Science City, Hi-Tech Industrial Zone Guangzhou, Guangdong CHINA TEL: [phone] FAX: [phone] Email: [e-mail]

#### Contact Person of the Submission:

Name: You Yijie Address: RM.1711, Building K, NO.101 Science Ave International Creative Valley Development Zone, Guangzhou China TEL: [phone] FAX: [phone] Email: [e-mail]

#### 2. Device Information

Type of 510(K) submission: Traditional Trade Name: Portable Electro-Stimulation Therapy Device Model: LGT-235 Regulation name: Transcutaneous electrical nerve stimulator for pain relief. Review panel: Neurology Product code: GZJ Requlation Class: II Regulation Number: 21 CFR 882.5890

#### 3. Predicate Device Information

510(k) submitter/holder: Mettler Electronics Corp. 510(K) Number: K111482 Regulation Class: 2 Device: Sonicator Plus 920 Sonicator Plus 920, Model ME 920 Trade name:

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### 4. Device description

The Portable Electro-Stimulation Therapy Device, model LGT-235 is a stimulator which sends gentle electrical current to underlying nerves via electrodes (Knee brace or self-adhesive electrode) applied on the skin with two operational modes and powered by rechargeable lithium battery; the device system is made up of mobile app MStim Arth, main unit and electrodes (Knee brace and self-adhesive electrode).

The Mobile App MStim Arth provides access to treatment controls for Portable Electro-Stimulation Therapy Device from a compatible mobile device for selecting a pre-programmed output mode and treatment time.

The main unit provides access to adjust the intensity up or down, put ON/OFF the main unit.

The two modes that Portable Electro-Stimulation Therapy Device, model LGT-235 employs are transcutaneous electrical stimulation (TENS) and Microcurrent (MCR).

TENS and MCR are both specifically targets the sensory nerves, which are responsible for sending pain signals to the brain. TENS and MCR use tiny electrical impulses sent through the skin to nerves to modify the pain perception. TENS and MCR do not cure any physiological problem; it only helps control the pain, this activates the underlying sensory nerves. Knee brace is placed on the leg or arm close to the area of pain.

### 5. Principle of operation:

The Portable Electro-Stimulation Therapy Device, model LGT-235 sends gentle electrical current to underlying nerves and muscle group via electrodes (Knee brace or self-adhesive electrode) applied on the skin and powered by rechargeable lithium battery. When used in TENS or MCR mode, it specifically targets the sensory nerves, which are responsible for sending pain signals to the brain; and it uses tiny electrical impulses sent through the skin to nerves to modify pain perception and finally helps control the pain.

#### 6. Indications for Use

Portable Electro-Stimulation Therapy Device, model LGT-235 is indicated for the Symptomatic relief of chronic intractable pain, Post-traumatic pain and Post-surgical pain of the arms and legs..

#### 7. Summary of technological characteristics of device compared to the predicate devices (K111482)

| Characteristic | Subject device | Predicate device | Discussion of difference | |
|--------------------------------------------|--------------------------------------------------------------------------------------------------------------------------------------------------------------|-----------------------------------------------------------------------------------------------------------------------------------------|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| | Present application<br>(Portable<br>Electro-Stimulation<br>Therapy Device, model | (K111482, Sonicator<br>Plus 920, Model ME<br>920 (TENS and<br>Microurrent mode)) | | |
| | LGT-235) | | | |
| Classification | 21 CFR 882.5890 | 21 CFR 890.5890 | Same | |
| Product Code | GZJ | GZJ | Same | |
| FDA Class | 2 | 2 | Same | |
| Intended Use | Symptomatic relief of<br>chronic intractable pain<br>2. Post-traumatic pain<br>3. Post-surgical pain | Symptomatic relief of<br>chronic intractable pain<br>2. Post-traumatic pain<br>3. Post-surgical pain | Same | |
| Principle of operation | sends gentle electrical<br>current to muscle group<br>via electrodes applied<br>on the skin | sends gentle electrical<br>current to muscle group<br>via electrodes applied<br>on the skin | Same | |
| target population | adults | adults | Same | |
| anatomical site | Arm and legs | Arm and legs | Same | |
| Material of Patient<br>contact components | <b>Electrodes:</b><br>Knee brace: OK cloth +<br>SBR + dacron<br>Conductive fabric:<br>Silver wire + nylon<br>Self-adhesive electrode:<br>conductive hydrogel | Electrode: conductive<br>hydrogel | Different<br>Knee brace was<br>demonstrated<br>biocompability safety by<br>passing ISO 10993-5 and<br>ISO 10993-10 tests. The<br>difference does not raise<br>the issue of product's<br>safety and effectiveness. | |
| where used | home | home | Same | |
| Design | Handheld | Desk type | Different<br>This difference existed will<br>not affect the safety and<br>effectiveness of the<br>proposed device | |
| Power Source | Rechargeable lithium<br>battery 3.7V | AC line | Different<br>The proposed device was<br>demonstrated electrical<br>safety by passing ANSI<br>AAMI ES60601-1. The<br>difference does not raise<br>the issue of product's<br>safety and effectiveness. | |
| Method of line<br>current isolation | N/A (3.7V rechargeable<br>lithium battery operated<br>device) | Double isolation | Different<br>This difference existed will<br>not affect the safety and<br>effectiveness of the<br>proposed device. | |
| Patient<br>Leakage | Normal<br>condition | < 1µA | Meet requirement of<br>ANSI/AAMI ES60601-1 | Similar<br>The proposed device was |
| Current | Single fault<br>condition | < 1μΑ | >50μΑ | demonstrated electrical<br>safety by meet the<br>requirement of chapter<br>8.7.4.7 of ANSI AAMI<br>ES60601-1. The<br>difference does not raise<br>the issue of product's<br>safety and effectiveness. |
| Number<br>of Output<br>Channels | Number | One | two | Different<br>This will not affect the<br>safety and effectiveness<br>of the proposed device |
| | Synchronous<br>s or<br>Alternating? | Synchronous | Synchronous | Same |
| Number of Output<br>Modes | | two (TENS + MCR) | two (TENS + MCR<br>modes) | Same |
| Regulated Current or<br>Regulated Voltage? | | Current | Current | Same |
| | Software/Firmware/Micr<br>oprocessor Control? | Yes | Yes | Same |
| Automatic Overload<br>Trip? | | Yes | Yes | Same |
| Automatic No-Load<br>Trip? | | Yes | Yes | Same |
| Automatic Shut Off? | | "On/Off" button | "On/Off" button | Same |
| | User Override Control? | No, On/Off | No, On/Off, Hold or Stop | Same |
| Indicator<br>Display | On/Off<br>Status? | Yes | Yes | Same |
| | Low Battery? | Yes | N/A | Different<br>This difference existed will<br>not affect the safety and<br>effectiveness of the<br>proposed device |
| | Voltage/<br>Current<br>Level? | Yes (on app) | Yes | Same<br>System validation<br>testing scenarios<br>covering mitigation of<br>wireless risks in<br>accordance with<br>RED were added to our<br>full system testing<br>protocol to ensure safe<br>and effective use. |
| | Timer Range (minutes) | 1~60 minutes | 0~60 minutes | Same |
| ANSI AAMI ES60601-1 | Yes | Yes | Same | |
| IEC 60601-1-2 | Yes | Yes | Same | |
| IEC 60601-2-10 | Yes | Yes | Same | |
| Weight | main unit: 120g<br>Charging case: 150g | 11(lbs.) | Different<br>The Weight will not affect<br>the safety and<br>effectiveness of the<br>proposed device | |
| Dimensions<br>(W x H x D) | 59mm (W) × 59mm (L) ×<br>22mm (H) (mm) | 4.9 x 13.6 x10.5(in.) | Different<br>The dimensions will not<br>affect the safety and<br>effectiveness of the<br>proposed device | |
| Operating<br>condition | Temperature: 5 to 40°C;<br>Rel. humidity: ≤80%;<br>Atmosphere Pressure:<br>86.0 to 106.0kPa. | Temperature of use from<br>10°C to 40°C<br>Max. relative humidity<br>from 30% to 75%<br>Atmospheric pressure<br>from 700 hPa to1060 hPa | Similar<br>The operating condition of<br>subject device has passed<br>the safety test, and the<br>Instructions for Use<br>provides the operating<br>condition, so the<br>difference between the<br>operating conditions of<br>subject device and<br>predicate device will not<br>affect the safety and<br>effectiveness of subject<br>device | |

#### Basic Device Characteristics - Comparison with Predicate Device

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# Output Specifications – Comparison with Predicate Device

| Characteristic | Subject device<br>Present application<br>(Portable<br>Electro-Stimulation<br>Therapy Device, model<br>LGT-235) | Predicate device<br>(K111482, Sonicator<br>Plus 920, Model ME<br>920 (TENS and<br>Microurrent mode)) | Discussion of difference | |
|----------------------------------------------------|----------------------------------------------------------------------------------------------------------------------------|-------------------------------------------------------------------------------------------------------------------|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| Waveform | Symmetrical biphasic | Symmetrical Biphasic | Same | |
| Maximum Output<br>Voltage (± 20%) | TENS:<br>50V @ 500 Ω<br>115 V @ 2 kΩ<br>125 V @ 10 kΩ<br>MCR:<br>0.45 V@ 500 Ω<br>1.8 V@ 2 kΩ<br>7.4 V @ 10 kΩ | TENS:<br>50 V @ 500 Ω<br>115 V @ 2 kΩ<br>125 V @ 10 kΩ<br>MCR:<br>0.37 V @ 500 Ω<br>1.5 V @ 2 kΩ<br>7.4 V @ 10 kΩ | Similar<br>The error existed in MCR<br>mode between proposed<br>device and predicate<br>device are acceptable.<br>The difference does not<br>raise the issue of<br>product's safety and<br>effectiveness. | |
| Maximum Output | TENS: | TENS: | | |
| Current (± 20%) | | 100 mA@ 500 Ω<br>58 mA@ 2 kΩ<br>13 mA@ 10 kΩ<br>MCR:<br>0.92 mA@ 500 Ω<br>0.90 mA@ 2 kΩ<br>0.74 mA@ 10 kΩ | 100 mA@ 500 Ω<br>58 mA@ 2 kΩ<br>13 mA@ 10 kΩ<br>MCR:<br>0.74 mA@ 500 Ω<br>0.75 mA@ 2 kΩ<br>0.74 mA@ 10 kΩ | The error existed in MCR<br>mode between proposed<br>device and predicate<br>device are acceptable.<br>The difference does not<br>raise the issue of<br>product's safety and<br>effectiveness. |
| Pulse Width | | TENS: 50 to 500 μs | TENS: 100 ~ 600us | Similar |
| | | MCR: 4.16 ms ~ 0.5s | MCR: 1.25ms ~ 1.67s | The predicate device is<br>safe and effective in pulse<br>width range 100 ~ 600us<br>for TENS mode and<br>1.25ms ~ 1.67s for MCR<br>mode, since the pulse<br>width range of proposed<br>device are in the range of<br>predicate device, the<br>proposed device is also<br>safe and effective with its<br>pulse width, therefore, the<br>difference does not raise<br>the issue of product's<br>safety and effectiveness. |
| Frequency | | TENS: 1 ~ 120 Hz | TENS: 0.5 ~ 250 Hz | Similar |
| | | MCR: 1 ~ 120 Hz | MCR: 0.3 ~ 400 Hz | The frequency range of<br>predicate device is<br>overriding the range of<br>proposed device, since<br>the predicate device is<br>safe and effective,<br>therefore the proposed<br>device is also safe and<br>effective, the difference<br>does not raise the issue of<br>product's safety and<br>effectiveness. |
| Maximum intensity | | 100mA | 100 mA | Same |
| For<br>multiphasic | Symmetrical<br>phases? | Yes | Yes | Same |
| waveforms<br>only | Phase<br>Duration<br>(include<br>units)<br>(state<br>range, if<br>applicable<br>) (both<br>phases, if<br>asymmetric<br>al) | TENS: 50 to 500 µs<br>MCR: 4.16 ms ~ 0.5s | TENS: 100 ~ 600us<br>MCR: 1.25ms ~ 1.67s | Similar |
| | | | | The predicate device is<br>safe and effective in pulse<br>width range 100 ~ 600us<br>for TENS mode and<br>1.25ms ~ 1.67s for MCR<br>mode, since the pulse<br>width range of proposed<br>device are in the range of<br>predicate device, the<br>proposed device is also<br>safe and effective with its<br>pulse width, therefore,<br>difference existed does<br>not raise the issue of<br>product's safety and<br>effectiveness. |
| Stimulating surface area<br>of electrode (minimum) | | 2500mm² (50mm,<br>square) | 2015.80mm² (50.8mm<br>diameter, round) | Similar<br>The smaller of the surface<br>area the higher risk is, the<br>difference does not raise<br>the issue of product's<br>safety and effectiveness. |
| Net Charge (µC/pulse) | | TENS:0µC @ 500Ω<br>MCR: 0µC@ 500Ω | 0 µC @ 500Ω | Same. |
| Maximum Phase<br>Charge (µC) | | TENS: 48 (µC) @ 500Ω<br>MCR: 34 (µC) @ 500Ω | TENS: 60 (µC) @ 500Ω<br>MCR: 75 (µC) @ 500Ω | Similar<br>The Maximum Phase<br>Charge of predicate<br>device is overriding the<br>proposed device, since<br>the predicate device is<br>safe and effective,<br>therefore the proposed<br>device is also safe and<br>effective, difference<br>existed does not raise the<br>issue of product's safety<br>and effectiveness. |
| Maximum Current<br>Density,<br>(mA / cm², r.m.s.) | | TENS: 0.81mA/cm2 @<br>500Ω<br>MCR: 0.036mA/cm2@<br>500Ω | TENS: 1.97 (mA/cm2)<br>@ 500Ω<br>MCR: 0.026mA/cm2 @<br>500Ω | Similar<br>For TENS mode, the<br>maximum current density<br>of proposed device is<br>overriding the proposed<br>device which means the<br>proposed device is safe<br>and effective. As for mode<br>MCR, the maximum<br>current density of<br>proposed device is little<br>bigger than predicate<br>device, however the<br>proposed device was<br>demonstrated safety by |
| | | | IEC 60601-2-10. The<br>difference does not raise<br>the issue of product's<br>safety and effectiveness. | |
| Maximum Power<br>Density (W/cm²) | TENS: 8.26 mW/cm²<br>@ 500Ω<br><br>MCR: 0.016 W/cm²<br>@ 500Ω | TENS: 39 mW/cm²<br>@ 500Ω<br><br>MCR: 0.007 mW/cm²<br>@ 500Ω | <b>Similar</b><br>For TENS mode, the<br>maximum power density<br>of proposed device is<br>overriding the proposed<br>device which means the<br>proposed device is safe<br>and effective. As for mode<br>MCR, the maximum<br>power density of proposed<br>device is bigger than<br>predicate device but far<br>less than 0.25 W/cm²<br>required by Guidance<br>Document for Powered<br>Muscle Stimulator (June<br>9, 1999), the difference<br>does not raise the issue of<br>product's safety and<br>effectiveness. | |

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#### 8. Discussion of Non-Clinical Tests Performed for Determination of Substantial Equivalence are as follows:

Non-clinical verification testing of the Portable Electro-Stimulation Therapy Device, model: LGT-235 included electrical, mechanical, and software tests to show the device meets its design specifications. Validation and performance testing validates that the device meets its user needs. Verification and validation test results established that the device meets its intended use, that it is as safe, as effective, and performs as well as the predicate devices, and that no new issues of safety and effectiveness were raised. The Portable Electro-Stimulation Therapy Device, model: LGT-235 was designed, verified, and validated according to the company's Design Control process and has been subjected to extensive safety and performance testing as shown in the test results provided in this submission. Verification and Validation testing data demonstrate that the device meets all of its specifications including compliance with the following standards:

- 1. ISO 10993-5:2009 Biological evaluation of medical devices Part 5: Tests for in vitro cytotoxicityISO 10993-10:2010 Biological evaluation of medical devices. Tests for irritation and skin sensitization
- 2. ANSI AAMI ES60601-1:2005/(R) 2012 and A1:2012 Medical electrical equipment. General requirements for basic safety and essential performance
- 3. IEC 60601-1-2:2014 Medical electrical equipment part 1-2: general requirements for safety - collateral standard: electromagnetic compatibility - requirements and tests
- 4. IEC 60601-2-10:2012 Medical Electrical equipment Part 2-10: Particular requirements for the safety of nerve and muscle stimulators
- 5. IEC 60601-1-11:2015 Medical electrical equipment Part 1-11: General requirements for basic safety and essential performance - Collateral Standard: Requirements for medical electrical equipment and medical electrical systems used in the home healthcare environment.

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#### 9. Conclusions

The electrical safety, EMC, biocompatibility, software verification and validation, basic unit characteristics, and output specifications information provided is sufficient to demonstrate substantial equivalence to the predicate device. As the Portable Electro-Stimulation Therapy Device, model: LGT-235 is nearly identical to the predicate device, differences in their characteristics do not raise any raise new questions regarding safety and effectiveness with identical indications for use and essentially identical technological characteristics, the Portable Electro-Stimulation Therapy Device, model: LGT-235 is substantially equivalent to the predicate device Sonicator Plus 920, Model ME 920 (TENS and MCR mode).