K172478 · Wat Medical Technology (Ningbo) Co., Ltd. · GZJ · Apr 19, 2018 · Neurology
Device Facts
Record ID
K172478
Device Name
TENS device-EmeTerm, CinvStop
Applicant
Wat Medical Technology (Ningbo) Co., Ltd.
Product Code
GZJ · Neurology
Decision Date
Apr 19, 2018
Decision
SESE
Submission Type
Traditional
Regulation
21 CFR 882.5890
Device Class
Class 2
Attributes
Therapeutic
Indications for Use
The EmeTerm CinvStop is a wearable device for the treatment of nausea and vomiting caused by motion sickness and pregnancy.
Device Story
Wearable TENS device worn on wrist; stimulates median nerve to treat nausea and vomiting. Device generates electric pulses with specific waveforms, frequency, and amplitude. Operated by patient via on-device controls for intensity adjustment. Provides electrical stimulation to nerves in wrist; intended to alleviate symptoms of motion sickness and pregnancy-related nausea. Benefits patient by providing non-pharmacological relief. Used in home or point-of-care settings.
Clinical Evidence
No clinical data provided. Substantial equivalence is supported by non-clinical bench testing, including electromagnetic safety (IEC 60601-1-2), electrical safety (IEC 60601-1, IEC 60601-1-11), and biocompatibility (ISO 10993-5, ISO 10993-10).
Technological Characteristics
Wearable TENS device; lithium battery powered. Delivers AC sharp wave electrical pulses; frequency 33Hz, phase duration 300us. Features adjustable intensity (5 levels), single channel output. Biocompatible materials per ISO 10993. Electrical safety per IEC 60601-1/1-11; electromagnetic compatibility per IEC 60601-1-2.
Indications for Use
Indicated for the treatment of nausea and vomiting caused by motion sickness and pregnancy in patients seeking relief.
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.
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July 15, 2021
WAT Medical Technology (Ningbo) Co., Ltd Rodney Zhang Cto Room703-711, No.2 North Taoyuan Road Ningbo, Zhejiang 315600 China
Re: K172478
Trade/Device Name: TENS device-EmeTerm, CinvStop Regulation Number: 21 CFR 882.5890 Regulation Name: Transcutaneous electrical nerve stimulator for pain relief Regulatory Class: Class II Product Code: GZJ
Dear Rodney Zhang:
The Food and Drug Administration (FDA) is sending this letter to notify you of an administrative change related to your previous substantial equivalence (SE) determination letter for your device cleared on April 19, 2018. Specifically, FDA is updating this SE letter due to a typo in the clearance date, which was incorrectly dated as April 19, 2019.
Please note that the 510(k) submission was not re-reviewed. For questions regarding this letter please contact Amber Ballard, OHT5: Office of Neurological and Physical Medicine Devices, by email (Amber.Ballard@fda.hhs.gov) or phone (240-402-9983).
Sincerely,
# Jitendra V. Virani -S
For Amber Ballard
Assistant Director DHT5B: Division of Neuromodulation and Physical Medicine Devices OHT5: Office of Neurological and Physical Medicine Devices Office of Product Evaluation and Quality Center for Devices and Radiological Health
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April 19, 2019
WAT Medical Technology (Ningbo) Co., Ltd Rodney Zhang CTO Room703-711, No.2 North Taoyuan Road Ningbo, 315600 Cn
Re: K172478
Trade/Device Name: TENS device-EmeTerm, CinvStop Regulation Number: 21 CFR 882.5890 Regulation Name: Transcutaneous Electrical Nerve Stimulator For Pain Relief Regulatory Class: Class II Product Code: GZJ Dated: March 15, 2018 Received: March 20, 2018
Dear Rodney Zhang:
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. 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 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); good manufacturing practice requirements as set forth in the quality systems (OS) regulation (21 CFR Part 820);
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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 the CDRH's Office of Surveillance and Biometrics/Division of Postmarket Surveillance.
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/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 (DICE@fda.hhs.gov) or phone (1-800-638-2041 or 301-796-7100).
Sincerely,
#### William J. Heetderks -S 2018.04.19 13:39:37 -04'00'
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) K172478
Device Name EmeTerm CinvStop
Indications for Use (Describe)
The EmeTerm CinvStop is a wearable device for the treatment of nausea and vomiting caused by motion sickness and pregnancy.
Prescription Use (Part 21 CFR 801 Subpart D)
X Over-The-Counter Use (21 CFR 801 Subpart C)
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Image /page/4/Picture/0 description: The image shows the logo for WAT Med. The logo consists of a stylized "W" in blue, green, and pink, followed by the text "WAT Med" in black. The text is in a bold, sans-serif font.
### 510 (k) SUMMARY OF SAFETY AND EFFECTIVENESS
(As Required by 21 CFR 807.92)
#### 1. Date Prepared [21 CFR 807.92(a)(1)]
04/11/2018
#### 2. Submitter's Information [21 CFR 807.92(a)(1)]
| Company Name: | WAT Medical Technology Inc. |
|------------------|----------------------------------------------------------------------------------|
| Company Address: | Room703-711, No.2 North Taoyuan Road, 315600<br>Ningbo, Zhejiang Province, P.R.C |
| Contact Person: | Rodney Zhang |
| Phone: | 86-574-6506-0811 |
| Email: | 13500799711@139.com |
#### 3. Trade Name, Common Name, Classification [21 CFR 807.92(a)(2)]
| Trade Name: | TENS device-EmeTerm |
|--------------------|---------------------|
| Common Name: | TENS device-EmeTerm |
| Model No. | YF-ZTY-E1 |
| Product Code: | GZJ |
| Regulation Number: | 21 CFR 882.5890 |
| Device Class: | II |
#### 4. Identification of Predicate Devices(s) [21 CFR 807.92(a)(3)[
The identification of predicates within this submission is as follow:
| Predicate I | |
|----------------------|---------------------------|
| Manufacturer: | Woodside Biomedical, Inc. |
| Trade Name: | ReliefBand Device |
| Product Code: | GZJ |
| Classification Name: | Neurology |
| Regulation Number: | 21 CFR 882.5890 |
| Classification: | Class II |
| FDA 510 (k) #: | K020180 |
### SECTION 1 - 2 of 6
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Image /page/5/Picture/0 description: The image contains the logo for WAT Med. The logo consists of a stylized "W" symbol in green and pink, followed by the text "WAT Med" in bold, black letters. The logo is simple and modern, with a focus on the company's name.
#### 5. Description of the Device [21 CFR 807.92(a)(4)]
TENS device-EmeTerm generates the electric pulses with highly specific waveforms, frequency and amplitude to stimulate the median nerve. The accurate pulse signals provide relief through electrical stimulation of the nerves in the patient's wrist.
There are several names formerly used by proposed product TENS device-EmeTerm. Previous names have been shown within various test reports include: EmeTerm-mo, EmeTerm-mo device for preventing and treating motion sickness, ZHITUYI (hand) and ZHITUYI (shell). The names listed above are all representing the test results of TENS device-EmeTerm.
#### 6. Previous Device Names and Company:
Previous Device Name:
There are several names formerly used by proposed product TENS device-EmeTerm. Previous names have been shown within various test reports include EmeTerm-mo, EmeTerm-mo device for preventing and treating motion sickness, ZHITUYI (hand) and ZHITUYI (shell). The names listed above are all representing the test results of TENS device-EmeTerm.
Previous Company:
The company appears in various test reports is WAT Medical Technology (Ningbo) Co., Ltd, which is the same company as the current WAT Medical Technology Inc.
#### 7. Indication for Use [21 CFR 807.92(a)(5)]
TENS device-EmeTerm is a wearable device for the treatment of nausea and vomiting caused by motion sickness and pregnancy.
#### 8. Non-Clinical Tests and Clinical Tests
N/A
| Non-Clinical Tests | Electromagnetic Safety Test (IEC 60601-1-2) |
|--------------------|--------------------------------------------------------|
| | Electronical Safety Test (IEC 60601-1, IEC 60601-1-11) |
| | Biocompatibility: In Vitro Cytotoxicity (ISO 10993-5) |
| | Biocompatibility: Skin Irritation (ISO 10993-10) |
| | Biocompatibility: Skin Sensitization (ISO 10993-10) |
Clinical Tests
## SECTION 1 - 3 of 6
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# W. WAT Med
#### 9. Technological Characteristics [21 CFR 807.92(a) and Substantial Equivalence Comparison [21 CFR 807.92(b)(1) and 807.92(b)(2)]
| Table 1 | Proposed Device | Predicate Device |
|--------------------|-------------------------------------------------------------------------------------------------------------------------------------|-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| Product Name | EmeTerm Device | ReliefBand Device |
| Product Code | GZJ | GZJ |
| Regulation No. | 21 CFR 882.5891 | 21 CFR 882.5890 |
| Classification | Class II | Class II |
| Indication for Use | TENS device-EmeTerm is a wearable<br>device for the treatment of nausea and<br>vomiting caused by motion sickness<br>and pregnancy. | The ReliefBand Devices are<br>indicated for over the counter use<br>in the relief of nausea and vomiting<br>(NV) due to motion sickness, and<br>for the relief of mild to moderate<br>nausea and vomiting associated<br>with pregnancy. |
| 510 (k) Number | N/A | K020180 |
| Table 2 | Proposed Device | Predicate Device | |
|----------------------------------------------------------------------|---------------------|-----------------------------------------------------|-----------------------------------------------------|
| Device Feature | | | |
| Device Name | EmeTerm Device | ReliefBand Device | |
| Power Source | One lithium battery | Two 3V lithium coin cells | |
| Follow Current | Yes | Yes | |
| Voltage Overload<br>Detection | Yes | Yes | |
| Adjustable Intensity | 5 | 5 | |
| Channel | 1 | 1 | |
| Operation<br>Tips | Start | Yes | Yes |
| | Low<br>Battery | Yes | Yes |
| | Work | Yes | Yes |
| User Control | | ON/OFF button on front<br>of device | ON/OFF button on front<br>of device |
| Patient override<br>control method | | On/Off and gear adjust button on front<br>of device | On/Off and gear adjust button on<br>front of device |
| Indicator displays | | Unit functioning<br>Electrical connection | Unit functioning<br>Electrical connection |
| Timer Setting | | Yes | Yes |
| Weight | | 29.5g | 34g |
| Dimensions | | 4.48*3.25*1.4cm | 3.81*5.08*1.14cm |
| Waveform | | AC Sharp Wave | AC Sharp Wave |
| Phase Duration (usec) | | 300us(±0.5%) | 300us(±0.5%) |
| Phase Interval | | 10us(±0.5%) | 10us(±0.5%) |
| Pulse Period | | 500us(±0.5%) | 505us(±0.5%) |
| Frequency (Hz) | | 33Hz(±0.5%) | 33Hz(±0.5%) |
| Net Charge (µC) per<br>pulse | | 0 | 0 |
| Maximum output<br>voltage (V):<br>@1000 ohms | | 38.2V(±0.5%) | 39.8V(±0.5%) |
| Maximum output<br>current (mA):<br>@1000 ohms | | 6mA(±0.5%) | 6mA(±0.5%) |
| Maximum phase<br>charge (µC) @1000Ω | | 1.78 | 1.8 |
| Maximum Current<br>Density, (mA/cm²,<br>r.m.s.) @1000Ω | | 4.30 | 4.32 |
| Maximum Average<br>Power Density,<br>(W/cm²) @1000Ω | 0.00002 | 0.00002 | |
| Maximum Average<br>Current (average<br>absolute value, mA)<br>@1000Ω | 0.5 | 0.5 | |
| Maximum Charge<br>Density (uC/ cm²)<br>@1000Ω | 1.28 | 1.3 | |
| Stimulating Surface<br>Areas<br>(cm²) | 2.709 | 2.72 | |
## SECTION 1 - 4 of 6
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# SECTION 1 - 5 of 6
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#### 10. Conclusion [21 CFR 807.92(b)(3)]
TENS device-EmeTerm is substantially equivalent to predicate device because both devices use identical technology and same intended use, also testing standards are identical with the predicates. The differences between both devices are insignificant in terms of safety and effectiveness.
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Open the Predicates tab for a family-tree view of predicate relationships. Click a node to trace its parents and children; selections from search carry over pre-selected. Commonly predicated devices are worth reading — a lot of people predicated them for a reason. The visual lineage is also handy on client calls, e.g. to show how a predicate family evolved and justify why your predicate still holds.
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Head to the search page and work through a few of these AI/ML fuzzy searches to build intuition: perivascular fat on CT · aortic valve calcification opportunistic screening on noncontrast CT · breast cancer prediction on digital pathology slides · autism detection · gestational age prediction · a hearing aid that can also detect a pulse · foundation model based analysis of ECG · large language models · penetration test. Watch how the relevance scores, intended use, and AI Performance tables tell you when results stop being meaningful.