K Number

Validate with FDA (Live)

Device Name

4 CHANNELS MULTIPLE MODEL DIGITAL ELECTRICAL STIMULATOR, MODEL NUVOSTIM IV, WL-2504A

Manufacturer

WELL-LIFE HEALTHCARE LIMITED

Date Cleared

2010-06-25

(129 days)

Product Code

Regulation Number

Type

Panel

Reference & Predicate Devices

K033857,K092763

Predicate For

N/A

Intended Use

The indication for use of this device includes the prescription TENS, NMS, Interferential stimulation as follows:

Transcutaneous Electrical Nerve Stimulator (TENS/IF TENS) & Program can be used for the following applications :

· For symptomatic relief of chronic intractable pain.

Neuromuscular electrical stimulation (NMS) & Program stimulation can be used for the following applications :

· Relax muscle spasms
· Prevent or retard disuse atrophy
Increase local blood circulation
· Re-educate muscles
Maintain or increase the range of motion

Device Description

The Well-Life 4 Channels Multiple Modes Electrical Stimulator/ Model: WL-2504A is the The Well-che of Channels Matiple Motion Leorve stimulator(TEMS) and Interferential Combination (IF) used for pain relief and/or powered muscle stimulator(EMS) by applying Stimulation (if ) ascu for pain rollor which are attached on the patient's skin. The output and waveform is adjustable according to the situation of patient.

The Well-Life 4 Channels Multiple Modes Electrical Stimulator/ Model: WL-250A consisted The Well-Life + Chamble Modisle Model Eloctive. The stimulus generator generator generator summer mainly of two parts. the stimulas gonorator, close. The output port transmits the output current oulput current Specificular to the patient's skin so as to transmit this stimulus current to the patient for pain relief or muscle stimulation of intended use purpose.

The Well-Life 4 Channels Multiple Modes Electrical Stimulator/ Model: WL-2504 includes The Well-Life + Channels Modes as mentioned on the comparison table. These its moin several unlerent operation modes as montonou on the microprocessor as its main control unit.

AI/ML Overview

Here's a breakdown of the acceptance criteria and the study information based on the provided 510(k) summary:

This device (Well-Life 4 Channels Multiple Modes Electrical Stimulator/ Model: NuvoStim IV, WL-2504A) is an electrical stimulator. The 510(k) summary focuses primarily on demonstrating substantial equivalence to predicate devices through technical specifications and compliance with voluntary standards, rather than a clinical study evaluating diagnostic accuracy or reader performance typically associated with AI/imaging devices.

Therefore, many of the requested points related to AI studies, ground truth, and expert adjudication are not applicable to this type of device submission.

Acceptance Criteria and Reported Device Performance

The acceptance criteria are not explicitly stated as distinct pass/fail thresholds in the provided text. Instead, the "performance" shown is in the form of electrical output ranges for various functions of the device, which are implicitly compared to the performance of predicate devices. The claim of the study is that these output characteristics are "identical" or "substantial equivalent" to the predicate devices.

Table of Acceptance Criteria and Reported Device Performance:

Function	Operation Function	Acceptance Criteria (Implicit)	Reported Device Performance (WL-2504A)
Current Density Range (mA/cm²) (measured against 500Ω loading at maximum pulse rate)	IF TENS	Output characteristics substantially equivalent to predicate (WL-2206D)	Minimum: < 0.001 Moderate: 0.0281 Maximum: 0.1125
	TENS	Output characteristics substantially equivalent to predicate (WL-2203A)	Minimum: < 0.001 Moderate: 0.09 Maximum: 0.18
	EMS	Output characteristics substantially equivalent to predicate (WL-2204A, WL-2204A-P2)	Minimum: < 0.001 Moderate: 0.1125 Maximum: 0.225
	Pre-program	Not explicitly linked to a single predicate, likely comparison to combined functions	Minimum: < 0.001 Moderate: 0.09 Maximum: 0.18
Power Density Range (W/cm²) (measured against 500Ω loading at maximum pulse rate)	IF TENS	Output characteristics substantially equivalent to predicate (WL-2206D)	Minimum: < 0.001 Moderate: 0.0281 Maximum: 0.1125
	TENS	Output characteristics substantially equivalent to predicate (WL-2203A)	Minimum: < 0.001 Moderate: 0.0018 Maximum: 0.0072
	EMS	Output characteristics substantially equivalent to predicate (WL-2204A, WL-2204A-P2)	Minimum: < 0.001 Moderate: 0.00281 Maximum: 0.01125
	Pre-program	Not explicitly linked to a single predicate, likely comparison to combined functions	Minimum: < 0.001 Moderate: 0.0018 Maximum: 0.0072
Voluntary Standards Compliance	N/A	Compliance to ANSI/AAMI, NS4-1985, EN 60601-1, and EN 60601-1-2	Complied with all listed standards.
Risk Assessment & Software Validation	N/A	Risk assessment carried out; Software verification/validation according to FDA guidance.	Carried out; Complied with guidance.

Study Details:

Sample size used for the test set and the data provenance:
- Test Set Sample Size: Not applicable. This submission relies on engineering and electrical output testing, not a clinical test set with patient data. The "test set" would be the device itself undergoing various electrical measurements.
- Data Provenance: Not applicable. The data is generated from laboratory testing of the device's electrical outputs.
Number of experts used to establish the ground truth for the test set and the qualifications of those experts:
- Number of Experts: Not applicable. Ground truth, in the sense of clinical interpretations or diagnoses, is not established for this type of submission. The "ground truth" here is the accurate measurement of electrical output according to standardized procedures.
- Qualifications of Experts: This would involve electrical engineers or technicians trained in performing these measurements and verifying compliance with standards. Their specific qualifications are not detailed in the summary.
Adjudication method (e.g. 2+1, 3+1, none) for the test set:
- Adjudication Method: Not applicable. This is not a study involving human interpretation or subjective assessments.
If a multi-reader multi-case (MRMC) comparative effectiveness study was done, If so, what was the effect size of how much human readers improve with AI vs without AI assistance:
- MRMC Study: No. This is not an AI or imaging device, so an MRMC study is irrelevant.
If a standalone (i.e. algorithm only, without human-in-the-loop performance) was done:
- Standalone Performance: Not applicable. This is an electrical stimulating device, not an algorithm.
The type of ground truth used (expert consensus, pathology, outcomes data, etc.):
- Type of Ground Truth: For this device, the "ground truth" for non-clinical testing refers to the established scientific principles and industry standards for electrical measurements, electrical safety, and electromagnetic compatibility. This would be verified by calibrated equipment and standard test protocols.
The sample size for the training set:
- Training Set Sample Size: Not applicable. This is not an AI device, so there is no "training set."
How the ground truth for the training set was established:
- Ground Truth Establishment for Training Set: Not applicable.

Summary

{0}------------------------------------------------

510(K) Summary

This 510(k) Summary is being submitted in accordance with the requirements of SMDA 1990 and 21 CFR 807.92.

The assigned 510(k) number is: K100399.

Submitter's Identifications:

Company Name:	Well Life Healthcare Limited
Contact person:	Jenny Hsieh
Address:	1FL., No.16, Lane 454, Jungjeng Rd., Yunghe City, Taipei County,
	Taiwan, R.O.C.
TEL No.:	886-2-2928-2112
Fax No.:	886-2-2928-1880
E-mail address:	jenny@welllifehealthcare.com.tw

1. Name of the Device:
  4 Channels Multiple Modes Electrical Stimulator/ Model: NuvoStim IV, WL-2504A
1. Information of the 510(k) Cleared Device (Predicate Device):
  WL-2203A (K033857), WL-2204A(K033857),WL-2204A -P2(K033857), and WL-2206D(K092763)
1. Device Description:
  The Well-Life 4 Channels Multiple Modes Electrical Stimulator/ Model: WL-2504A is the The Well-che of Channels Matiple Motion Leorve stimulator(TEMS) and Interferential Combination (IF) used for pain relief and/or powered muscle stimulator(EMS) by applying Stimulation (if ) ascu for pain rollor which are attached on the patient's skin. The output and waveform is adjustable according to the situation of patient.

1. Intended Use:
  The indication for use as described hereafter :

Transcutaneous Electrical Nerve Stimulator (TENS) & Program can be used for the following applications :

Tonowing upplications intractable pain ---------------------------------------------------------------------------------------------------------------------------------------

Neuromuscular electrical stimulation (NMS) & Program stimulation can be used for the following applications :

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

Relax muscle spasms
Prevent or retard disuse atrophy
· Increase local blood circulation
· Re-educate muscles
· Maintain or increase the range of motion

6. Substantial Equivalence Comparison

The WL-2504A has output characteristics and controls that are identical to those of the The WL-2504A has output online of the considered as Substantial Equivalent to the function of chosen 510K chosen predicate devices:

lunction of GRSSH 8 for chools procession is substantial equivalent to WL-2203A (KO33857).

2> The NMS function of WL-2504A is substantial equivalent to WL-2204A (K033857).

2> The Nill Tunction of WL-2504A is substantial equivalent to WL-2204A-P2 (K03387).

4> The IF TENS function of WL-2504A is substantial equivalent to WL-2206D (K092763).

7. Output Performance Range for each Operation Mode

Current Density Range: Unit mA/cm²..(measured against 500Ω loading at maximum . oulse rate).

Function	Operation Function
	IF TENS	TENS	EMS	Pre-program
Minimum	< 0.001	< 0.001	< 0.001	< 0.001
Moderate	0.0281	0.09	0.1125	0.09
Maximum	0.1125	0.18	0.225	0.18

Power Density Range: Unit W/cm² (measured against 500Ω loading at maximum pulse rate).

Function	Operation Function
	IF TENS	TENS	EMS	Pre-program
Minimum	< 0.001	< 0.001	< 0.001	< 0.001
Moderate	0.0281	0.0018	0.00281	0.0018
Maximum	0.1125	0.0072	0.01125	0.0072

1. Discussion of Non-Clinical Tests Performed Determination of Substantial Equivalence are as follows:
  Compliance to applicable voluntary standards includes ANSI/AAMI, NS4-1985, as well as EN 60601-1, and EN 60601-1-2 requirement.

In addition to the compliance of voluntary standards, the risk assessment has been carried in addition to the compliance of volunally clanted verification has been carried out according to the FDA software validation guidance.

1. Conclusions
  Conclusions
  The 4 Channels Multiple Modes Electrical Stimulator , model WL-2504A , has the same The 4 Channels Multiple Mouter Liectives Citing of Children of WL-2203A (K033857),
  intended use and technological characteristics as the cleared device of Mercever intended use and technological characteriorions and WL-2206D (K092763). Moreover, WL-2204A (K035657),VL-2204/ 1 2(1000001)), at this submission demonstrate that the difference ventication and validation tests containous in the submitted models could maintain the same safety and effectiveness as that of cleared device.

In the other words, those engineering difference do not: (1) affect the intended use or (2) alter the fundamental scientific technology of the device.

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

Image /page/2/Picture/1 description: The image shows the logo for the U.S. Department of Health & Human Services. The logo consists of a stylized caduceus symbol, which is a staff with two snakes coiled around it, representing medicine and healing. The logo is encircled by the text "DEPARTMENT OF HEALTH & HUMAN SERVICES - USA" in a circular arrangement.

Food and Drug Administration 10903 New Hampshire Avenue Document Control Room -WO66-G609 Silver Spring, MD 20993-0002

JUN 2 5 2010

Well-Life Healthcare Limited c/o Ms. Jenny Hsieh Official Correspondent 1FL, No.16, Lane 454, Jungjeng Road Yunghe City, Taipei County China (Taiwan)

Re: K100399

Trade/Device Name: 4 Channels Multiple Modes Electrical Stimulator / Model: NuvoStim IV, WL-2504A Regulation Number: 21 CFR 882.5890 Regulation Name: Transcutaneous Electrical Nerve Stimulator for Pain Relief Regulatory Class: Class II Product Codes: GZJ, IPF, LIH Dated: May 27, 2010 Received: May 28, 2010

Dear Ms. Hsieh:

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. Iisting 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.

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

Page 2 - Ms. Jenny Hsieh

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 (reporting of medical device-related adverse events) (21 CFR 803); good manufacturing practice requirements as set forth in the quality systems (QS) regulation (21 CFR Part 820); and if applicable, the electronic product radiation control provisions (Sections 531-542 of the Act); 21 CFR 1000-1050.

If you desire specific advice for your device on our labeling regulation (21 CFR Part 801), please go to http://www.fda.gov/AboutFDA/CentersOffices/CDRH/CDRHOffices/ucm115809.htm for the Center for Devices and Radiological Health's (CDRH's) Office of Compliance. Also, please note the regulation entitled, "Misbranding by reference to premarket notification" (21CFR 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.

You may obtain other general information on your responsibilities under the Act from the Division of Small Manufacturers, International and Consumer Assistance at its toll-free number (800) 638-2041 or (301) 796-7100 or at its Internet address

http://www.fda.gov/MedicalDevices/Resourcesfor You/Industry/default.htm.

Sincerely yours.

Kesia Alexander

Malvina B. Eydelman, M.D. Director Division of Ophthalmic, Neurological, and Ear, Nose and Throat Devices Office of Device Evaluation Center for Devices and Radiological Health

Enclosure

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

Indications For Use

k 100399 510(k) Number (if known):

Device Name: 4 Channels Multiple Modes Electrical Stimulator / Model: NuvoStim IV, WL-2504A