PMS(1 ~ 2): It is intended to stimulate healthy muscles in order to improve and facilitate muscle performance. TENS(3 ~ 5): To be used for temporary relief of pain associated with sore and aching muscles in the shoulder, waist, back, arm and leg due to strain from exercise or normal household work activities by applying current to stimulate nerve.

Heating: The Heating Lumbar Therapy Cushion is intended for temporary relief of minor aches and pains.

Device Description

The Heating Lumbar Therapy Cushion is a portable TENS/PMS device is equipped with a remote control, an adapter, a pair of electrode pads and electrode wire. The electrode wire is used to connect the electrode pads to the main unit.

The device has 5 stimulate modes and one heating mode, through the stainless steel plate to provide users with lower back stimulation and heat generation to warm and comfortable lower back muscles. In addition, it is equipped with a pair of electrode pads, which can be used to stimulate different parts of the body (the shoulder, waist, back, arm and leg).

The principle of operation of the subject device is:

PMS: A powered muscle stimulator for muscle conditioning is a device used for other than medical purposes to apply an electrical current to electrodes on a person's skin to temporarily affect the stimulated muscle's contractile properties, force output, and/or fatigue resistance. This device is not intended for use in patients with medical conditions and is intended only for muscle conditioning purposes.

TENS: The electrodes placed on the skin send small-scale, low-voltage electrical pulses to specific nerves. The purpose is to change the way neurons send signals and prevent pain signals from reaching the brain to relieve pain.

All the functions of the device can only be controlled by the remote control, which should connected to the main unit through a wire. The remote controller has the component of ON/OFF Key, Mode Selection key (left and right), Intensity Modification keys (increase and decrease) and an LCD screen. And the LCD screen can show stimulation mode, stimulation intensity, heating intensity and time remaining of an application mode. The device has 5 stimulation modes, each with 50 stimulation intensity and one heating Mode, heating mode has 3 levels, namely level 1 (37°C), level 2 (40°C), and level 3 (43°C).

The stainless steel plate provides users with lower back stimulation and heat to warm and comfort the muscles of the lower back. The stimulation function and heating function can be used separately or simultaneously. When used with a pair of electrode pads, it must be used simultaneously with the main unit stimulation mode, otherwise the electrode pads will be invalid.

The equipment has four models: AST-622, AST-622B, AST-623B, the four models differ only in appearance.

AI/ML Overview

This document is a 510(k) Premarket Notification from the FDA for a medical device called "Heating Lumbar Therapy Cushion." It establishes substantial equivalence to predicate devices, thus allowing the device to be marketed. However, it does not contain a study that establishes acceptance criteria and then proves the device meets those criteria through clinical trials or performance assessments that generate quantitative results against those criteria.

Instead, the document focuses on demonstrating that the device is "substantially equivalent" to existing, legally marketed predicate devices. This is achieved primarily through a comparison of technical specifications and performance characteristics, along with verification through non-clinical testing against relevant standards.

Therefore, I cannot provide the requested information for acceptance criteria and a study proving those criteria are met in the format requested, as that type of information is not present in this document. The document confirms that non-clinical tests were performed to assure conformance with standards, but it does not report specific performance metrics or acceptance criteria for those tests in a table as requested.

The document explicitly states:

"6.2 Discussion of Clinical Tests Performed: There were no Clinical Tests."

This means there's no clinical study described that would involve sample sizes, data provenance, expert adjudication, MRMC studies, standalone algorithm performance, or ground truth establishment in the context of clinical outcomes or diagnostic accuracy.

The tables provided (Elements of Comparison) list various technical specifications and note whether they are "SE" (Substantially Equivalent) or provide a value for comparison. However, these are not pre-defined acceptance criteria in the sense of demonstrating a certain level of clinical performance or accuracy against a ground truth. They are comparisons to predicate devices to establish equivalence.

In summary, the provided document does not contain the information required to answer your request regarding acceptance criteria and a study proving the device meets them, because it does not describe such a study.

Summary

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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 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.

December 13, 2021

Shenzhen OSTO Technology Company Limited % Cassie Lee Official Correspondent Guangzhou GLOMED Biological Technology Co., Ltd. 2231, Building 1, Rui Feng Center, Kaichuang Road, Huangpu District Guangzhou, Guangdong 510663 China

Re: K211942

Trade/Device Name: Heating Lumbar Therapy Cushion (Model: AST-622, AST-623, AST-623B) Regulation Number: 21 CFR 890.5850 Regulation Name: Powered muscle stimulator Regulatory Class: Class II Product Code: NGX, NUH, IRT Dated: December 6, 2021 Received: December 10, 2021

Dear Cassie Lee:

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

U.S. Food & Drug Administration 10903 New Hampshire Avenue Silver Spring, MD 20993 www.fda.gov

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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/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 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 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 Dean, PhD Assistant Director, Acute Injury Devices Team 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

Enclosure

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Indications for Use

510(k) Number (if known) K211942

Device Name

Heating Lumbar Therapy Cushion (Model: AST-622, AST-622B, AST-623, AST-623B)

Indications for Use (Describe)

Heating: The Heating Lumbar Therapy Cushion is intended for temporary relief of minor aches and pains.

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) X

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510(k) Summary for K211942

This summary of 510(k) safety and effectiveness information is being submitted in accordance with the requirement of 21 CFR 807.92.

1. Submitter's Information

510(k) Owner's Name: Shenzhen OSTO Technology Company Limited �
Establishment Registration Number: 3011564440 �
� Address: No.43 Longfeng Road, Xinsheng Community, Longgang Street, Longgang District, Shenzhen City, Guangdong Province, China
� Tel: +86-755-29769546
� Fax: +86-755-29769540
Contact Person: Li Yang (General Manger) �
Email: annaosto@163.com �

2. Application Correspondent:

Contact Person: Ms. Cassie Lee �
Guangzhou GLOMED Biological Technology Co., Ltd. �
Address: 2231, Building 1, Rui Feng Center, Kaichuang Road, Huangpu District, Guangzhou, � Guangdong, China
� Tel: +86 20 8266 2446
Email: regulatory@glomed-info.com �

3. Subject Device Information

Common Name: Powered Muscle Stimulator for Muscle Conditioning, and heating for pain relief, � blood circulation, and muscle performance
� Trade Name: Heating Lumbar Therapy Cushion (Model: AST-622B, AST-622B, AST-623B)
Classification Name: Stimulator, Nerve, Transcutaneous, Over-The-Counter �
� Review Panel: Physical Medicine
Product Code: NGX, NUH, IRT �
� Regulation Number: 890.5850
� Regulation Class: II

4. Predicate Device Information

Predicate Device 1 Information

Common Name: Transcutaneous electrical nerve stimulator for pain relief �
510(k) Number: K190783 �
Sponsor: Shenzhen OSTO Technology Company Limited �
� Trade Name: Health Expert Electronic Stimulator (model: AST-300L)
� Classification Name: Stimulator, Nerve, Transcutaneous, Over-the-Counter
� Review Panel: Neuroloqy, Physical Medicine
Product Code: NUH, NGX �
Regulation Number: 882.5890, 890.5850 �
� Regulation Class: II

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Predicate Device 2 Information

Common Name: Transcutaneous Electrical Nerve Stimulation (TENS) unit, Powered Muscle � Stimulation (PMS) unit, and heating for pain relief, blood circulation, and muscle performance
510(k) Number: K200561 �
� Sponsor: JKH Health Co., LTD
� Trade Name: StimPlus Patch
Classification Name: Stimulator, Nerve, Transcutaneous, Over-The-Counter �
� Review Panel: Neurology
� Product Code: NUH, NGX, NYN, IRT
Regulation Number: 882.5890 �
� Regulation Class: II

4. Device Description

The principle of operation of the subject device is:

The equipment has four models: AST-622, AST-622B, AST-623B, the four models differ only in appearance. Please refer to the photographs as below:

Model	Appearance	Model	Appearance

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Image /page/5/Figure/0 description: The image shows four different versions of a product, labeled AST-622, AST-622B, AST-623, and AST-623B. Each version appears to be a contoured pad or support with a distinct design. The AST-622 version has a smooth surface with recessed areas, while the AST-622B version has a similar shape but with circular indentations on the surface. The AST-623 and AST-623B versions have a different recessed design, with the AST-623B version also featuring circular indentations.

5. Intended Use / Indications for Use

PMS(1 ~ 2): It is intended to stimulate healthy muscles in order to improve and facilitate muscle performance.

TENS(3 ~ 5): To be used for temporary relief of pain associated with sore and aching muscles in the shoulder, waist, back, arm and leq due to strain from exercise or normal household work activities by applying current to stimulate nerve.

Heating: The Heating Lumbar Therapy Cushion is intended for temporary relief of minor aches and pains.

6. Test Summary

6.1 Non-Clinical Tests Performed

Non-Clinical tests were performed on the subject device in order to validate the design and to assure conformance with the following voluntary design standards in connection with medical device electrical safety, and electromagnetic compatibility:

Electrical safety test according to IEC 60601-1, IEC 60601-1-11 and IEC 60601-2-10 standards �
◆ Electromagnetic compatibility test according to IEC 60601-1-2 standard
� Usability test according to IEC 62366 standard
� Software verification and validation test according to the requirements of the FDA "Guidance for the Content of Premarket Submissions for Software Contained in Medical Devices"

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� The waveform test has also been conducted to verify the output specifications of the device according to "Guidance for Transcutaneous Electrical Nerve Stimulator for Pain Relief Intended for Over the Counter Use and Guidance for Powered Muscle Stimulator for Muscle Conditioning".
� Biocompatibility test according to ISO 10993-5 and ISO 10993-10 standards

6.2 Discussion of Clinical Tests Performed

There were no Clinical Tests.

7. Comparison to predicate device and conclusion

The technological characteristics, features, specifications, materials, mode of operation, and intended use of Heating Lumbar Therapy Cushion (Model: AST-622, AST-623, AST-623B) is substantially equivalent to the predicate devices quoted above.

The differences between the subject device and predicate devices do not raise new issues of safety or effectiveness.

Elements ofComparison	Subject Device	Predicate Device 1	Predicate Device 2	Remark
Device Name	Heating Lumbar TherapyCushion (Model: AST-622,AST-622B, AST-623, AST-623B)	Health Expert ElectronicStimulatorModel: AST-300L	PL-029K29, PL-029K30,and PL-029Q	--
510(k) Number	K211942	K190783	K200561	--
Intended Use	PMS(1 ~ 2): It is intended tostimulate healthy muscles inorder to improve andfacilitate muscleperformance.TENS(3 ~ 5): To be used fortemporary relief of painassociated with sore andaching muscles in theshoulder, waist, back, armand leg due to strain fromexercise or normalhousehold work activities byapplying current to stimulatenerve.Heating: The HeatingLumbar Therapy Cushion isintended for temporary reliefof minor aches and pains.	PMS (Mode 1~~8)It is intended to stimulatehealthy muscles in orderto improve and facilitatemuscle performance.TENS (Mode 9~~25)To be used for temporaryrelief of pain associatedwith sore and achingmuscles in the shoulder,waist, back, back of theneck, arm, leg, and footdue to strain fromexercise or normalhousehold work activitiesby applying current tostimulate nerve.	TENS:PL-029K29, PL-029K30,and PL-029Q are usedfor temporary relief ofpain associated withsore and aching musclesin the shoulder, waist,back, arm, and leg, dueto strain from exercise ornormal household andwork activities.PL-029K29, PL-029K30,and PL-029Q are alsointended forsymptomatic relief andmanagement of chronic,intractable pain andrelief of pain associatedwith arthritis.PMS:PL-029K29, PL-029K30,and PL-029Q are usedto stimulate healthymuscles in order to	SE
Elements ofComparison	Subject Device	Predicate Device 1	Predicate Device 2	Remark
			improve andfacilitate muscleperformance. To beused for theimprovement of muscletone and firmness, andfor strengtheningmuscles in the arms,abdomen, legs, andbuttocks. Not intendedfor use in any therapy orfor the treatment of anymedical conditions ordiseases.PL-029K29, PL-029K30,and PL-029Q are alsointended to temporarilyincrease local bloodcirculation in the healthymuscles of lowerextremities.Heating:PL-029K30 and PL-029Q is intended fortemporary relief of minoraches and pains.
Treatment site	Shoulder, waist, back, armand leg	Shoulder, waist, back,back of the neck, arm,leg, and foot	Arms, abdomen,shoulder, waist, back,and leg	SE
Principle ofOperation	PMS: A powered musclestimulator for muscleconditioning is a deviceused for other than medicalpurposes to apply anelectrical current toelectrodes on a person'sskin to temporarily affect thestimulated muscle'scontractile properties, forceoutput, and/or fatigueresistance. This device isnot intended for use inpatients with medicalconditions and is intended	PMS: A powered musclestimulator for muscleconditioning is a deviceused for other thanmedical purposes toapply an electrical currentto electrodes on aperson's skin totemporarily affect thestimulated muscle'scontractile properties,force output, and/orfatigue resistance. Thisdevice is not intended foruse in patients with	PMS: A powered muscle SEstimulator for muscleconditioning is a deviceused for other thanmedical purposes toapply an electricalcurrent to electrodes ona person's skin totemporarily affect thestimulated muscle'scontractile properties,force output, and/orfatigue resistance. Thisdevice is not intendedfor use in patients withmedical conditions andis intended only for
Elements ofComparison	Subject Device	Predicate Device 1	Predicate Device 2	Remark
only for muscle conditioningpurposes; TENS: Theelectrodes placed on theskin send small-scale, low-voltage electrical pulses tospecific nerves. Thepurpose is to change theway neurons send signalsand prevent pain signalsfrom reaching the brain torelieve pain.	medical conditions and isintended only for muscleconditioning purposes;TENS: The electrodesplaced on the skin sendsmall-scale, low-voltageelectrical pulses tospecific nerves. Thepurpose is to change theway neurons sendsignals and prevent painsignals from reaching thebrain to relieve pain.	muscle conditioningpurposes; TENS: Theelectrodes placed on theskin send small-scale,low-voltage electricalpulses to specificnerves. The purpose isto change the wayneurons send signalsand prevent pain signalsfrom reaching the brainto relieve pain.
Power Source(s)	Powered by adapter, 100-240VAC, 50-60HzOutput: 5Vdc, 2AUnit Input: 5Vdc, 2A	Adaptor Input:100-240Vac, 50-60Hz,0.1AOutput: 5Vdc, 2AUnit Input: 5Vdc, 2A	Rechargeable ornonrechargeable battery	SE
-Method of LineCurrent Isolation	Type BF Applied Part	Type BF Applied Part	Battery Supply	SE
-PatientLeakageCurrent	NC	AC: 54.4uA, DC: 0	AC: 54.5, DC: 0.5	2.0μΑ	SENote 1
	SFC	AC: 13.4uA, DC: 0	AC: 54.5, DC: 0.5	<10.0μΑ	SE
Number of OutputChannels:	1	2	1-2	SE
Number of OutputModes	For stimulation: 5 modesFor heating: 1 mode	25	PL-029K29: 8PL-029K30: 8PL-029Q: 8	SENote 2
Output IntensityLevel	For stimulation: 50 levelsFor heating: 3 levels	99 steps	No publicly available	SENote 1
Synchronous orAlternating	Synchronous	Synchronous	Synchronous	SE
Method of ChannelIsolation	1	2	1	SE
Regulated Currentor RegulatedVoltage?	Voltage	Voltage Control	Voltage	SE
Software/Firmware/MicroprocessorControl?	Yes	Yes	Yes	SE
Elements ofComparison	Subject Device	Predicate Device 1	Predicate Device 2	Remark
Automatic OverloadTrip	No	No	No	SE
Automatic No-LoadTrip	No	No	Yes	SE
Automatic Shut Off	Yes	Yes	Yes	SE
User OverrideControl	Yes	Yes	Yes	SE
IndicatorDisplay	On/OffStatus	Yes	Yes	Yes	SE
	Lowbattery	No	No	Yes	SE
	Voltage /currentlevel	Yes	Yes	No	SE
Timer Range		5-30 min	25 to 60 min	PL-029K29: 10~~60PL-029K30: 10~~60PL-029Q: 10~60	SE
Weight		Unit: 1704.5gRemote Controller: 73g	2.1Kg (Withoutaccessories)	Not publicly available	SENote 2
Dimensions(mm) [Lx Wx D]		Model AST-622 and AST-622B:456mm×354mm×86.7mmModel AST-623 and AST-623B:448.9mm×347.9mm×69.9mmStainless steel:For AST-622:224mm×96mmFor AST-622B:224mm×96mmFor AST-623:212mm×94mmFor AST-623B:212mm×94mm	429.2mm x 401mm x152.8mmFoot Conductive Rubber:254×98mm	PL-029K29: 150x80x12PL-029K30: 80x55x20PL-029Q: 148x81x29	SENote 2
Housing Materialsand Construction		Main unit: ABS Plastic,Stainless steelRed Transparent Plastic:	Main unit (Sole MassageRoller, Unit Housing,	Silicone & ABS	SE
Elements ofComparison	Subject Device	Predicate Device 1	Predicate Device 2	Remark
	ABS plasticElectrode Pads: White silicagel, Black conductivesilicone, Transparentconductive adhesivesilicone, Transparent PETsilicone	Host keypads): ABSplasticFoot Conductive pad:Stainless steelRed Transparent Plastic:ABS plasticElectrode Pads: Whitesilica gel, Blackconductive silicone,Transparent conductiveadhesive silicone,Transparent PET silicone
Maximum skintemperature	43°C	40°C	PL-029K30: 43°CPL-029Q: 43°C	SE
Waveform	Symmetrical Biphasic	Pulsed, symmetric,biphasic	Biphasic	SE
Shape	Rectangular	Rectangular, withinterphase interval	Rectangular	SE
Maximum OutputVoltage	23.2V±10% @ 500Ω	44V±10% @ 500Ω	Mode 1: This modecycles the followingmodesMode 2: 36.4Mode 3: 47.6Mode 4: 57.6Mode 5: 29.6Mode 6: 29.6Mode 7: 40.8Mode 8: 24.0	SENote 1
	39.2V±10% @ 2KΩ	80V±10% @ 2KΩ	Mode 1: This modecycles the followingmodesMode 2: 80.8Mode 3: 96.0Mode 4: 93.6Mode 5: 66.4Mode 6: 66.4Mode 7: 86.4Mode 8: 53.6
	73.2V±10% @ 10KΩ	112V±10% @ 10KΩ	Mode 1: This modecycles the followingmodesMode 2: 134Mode 3: 132Mode 4: 108Mode 5: 126
Elements ofComparison	Subject Device	Predicate Device 1	Predicate Device 2	Remark
			Mode 6: 126Mode 7: 129Mode 8: 105
Maximum OutputCurrent	46.4mA±10% @ 500Ω	88mA±10% @ 500Ω	Mode 1: This modecyclesthe following modesMode 2: 72.8Mode 3: 95.2Mode 4: 115.2Mode 5: 59.2Mode 6: 59.2Mode 7: 81.6Mode 8: 48.0	SENote 1
	19.6mA±10% @ 2KΩ	40mA±10% @ 2KΩ	Mode 1: This modecyclesthe following modesMode 2: 40.4Mode 3: 48.0Mode 4: 46.8Mode 5: 33.2Mode 6: 33.2Mode 7: 43.2Mode 8: 26.8
	7.32mA±10% @ 10KΩ	11.2mA±10% @ 10KΩ	Mode 1: This modecyclesthe following modesMode 2: 13.4Mode 3: 13.2Mode 4: 10.8Mode 5: 12.6Mode 6: 12.6Mode 7: 12.9Mode 8: 10.5
Pulse Duration	180µs	120µs	100µs	SENote 1
Pulse frequency(Hz)	133Hz	77.3Hz	Mode 1: This modecyclesthe following modesMode 2: 62.5Mode 3: 12.8~54.3Mode 4: 1.19Mode 5: 104.1Mode 6: 104.1Mode 7: 19.8Mode 8: 156.2	SENote 1
Net Charge (perpulse)	0μC @ 500Ω,Method: Balanced waveform	0µC @ 500Ω,Method: Balanced	Not publicly available	SE
Elements ofComparison	Subject Device	Predicate Device 1	Predicate Device 2	Remark
		waveform
Maximum PhaseCharge(µC) at 500Ω	8.352μC @ 500Ω	10.56µC @ 500Ω	Mode 1: This mode SEcyclesthe following modesMode 2: 14.6Mode 3: 19.0Mode 4: 23.0Mode 5: 11.8Mode 6: 11.8Mode 7: 16.3Mode 8: 9.6	SENote 1
Maximum CurrentDensity	4.44mA @ 500Ω	1.63mA @ 500Ω	Mode 1: This mode SEcyclesthe following modesMode 2: 2.02Mode 3: 2.64Mode 4: 3.20Mode 5: 1.64Mode 6: 1.64Mode 7: 3.26Mode 8: 1.92	SENote 1
Maximum PowerDensity	0.225mW/cm² @ 500Ω	0.0000266mW/cm² @500Ω	Mode 1: This mode SEcyclesthe following modesMode 2: 0.92Mode 3: 0.32~1.37Mode 4: 0.04Mode 5: 1.01Mode 6: 1.01Mode 7: 0.53Mode 8: 1.44	SENote 1
ON Time	2s	240 us	3.4~20	SENote 2
OFF Time	2s	12700 us	1~2.5	SENote 2
Biocompatibility	ISO 10993-5,ISO 10993-10	All user directlycontactingmaterials are compliancewith ISO10993-5 andISO10993-10requirements.	ISO 10993-5,ISO 10993-10	SE
Electrical Safety	IEC 60601-1,IEC 60601-1-11,IEC 60601-2-10	Comply with IEC 60601-1 and IEC 60601-2-10	IEC 60601-1,IEC 60601-2-10	SE
EMC	IEC 60601-1-2	Comply with IEC 60601-1-2	IEC 60601-1-2	SE

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Comparison in Detail(s):

Note 1:

Although the "Power Source(s)", "Patient Leakage Current", "Output Intensity Level", "Maximum Output Voltage", "Maximum Output Current", "Pulse Duration", "Pulse frequency (Hz)", "Maximum Phase Charge(uC) at 500Ω", "Maximum Current Density" and "Maximum Power Density" of subject device are a little different from the predicate device, but they all meet the requirements by IEC 60601-1-2 and IEC 60601-2-10 standards required. So the differences will not raise any safety or effectiveness issue.

Note 2:

Although the "Weight", "Dimensions(mm)", "Number of Output Modes", "ON Time" and "OFF Time" of subject device are a little different from the predicate device, but the differences will not raise any safety or effectiveness issue.

Comparison in Detail(s):

Note (a):

Although the "Pulse Duration", "Pulse Frequency" "On time" of subject device are little different from the predicate device, they are very similar in waveform group, and are all comply with IEC 60601-1 and IEC 60601-2-10 requirements. So the differences of the function specifications will not raise any safety or effectiveness issue.

Note (b):

Although the "Maximum Output Voltage", "Maximum Output Current","Maximum Phase Charge", "Maximum Average Current", "Maximum Current Density" and "Maximum Average Power Density" of subject device is little different from the predicate device, their maximum peak voltage are very similar, and are all comply with IEC 60601-2-10 requirements. So the differences of the function specifications will not raise any safety or effectiveness issue.

Finial Conclusion:

The subject devices "Heating Lumbar Therapy Cushion, model AST-622, AST-622B, AST-623, AST-623B" are Substantial Equivalent to the predicate device K190783 and K200561.

8. Date of the summary prepared: December 13, 2021

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).