LF900 is intended for use by medical professionals and patients at home, who are under medical supervision, in treating many conditions, such as: Primary lymphedema, Edema following trauma and sport injuries, Postimmobilization edema, venous insufficiencies, Lymphedema.

Device Description

This product is an Intermittent Pneumatic Compression system to improve the blood circulation of the human body. The operating principle is that the air from the device will be delivered to the sleeve with 4 air chambers and the air pressurizes sequentially the chambers from 1st to 4th.

AI/ML Overview

The provided FDA 510(k) clearance letter and summary for the LF900 Powered Inflatable Tube Massager does not describe a study that proves the device meets acceptance criteria in the way typically expected for AI/ML or diagnostic devices. Instead, it demonstrates substantial equivalence to a predicate device through non-clinical testing.

Here's an breakdown based on your requested information, highlighting what is and is not present in the document:

Acceptance Criteria and Study for LF900 Powered Inflatable Tube Massager

This submission is for a Powered Inflatable Tube Massager, not an AI/ML or diagnostic device. Therefore, the "acceptance criteria" and "study" are focused on demonstrating substantial equivalence to a previously cleared predicate device, primarily through non-clinical performance and safety testing, rather than a clinical effectiveness study with ground truth establishment in the context of diagnostic accuracy.

The key change in the LF900 (K231437) from a previous version (K203019) is a change in maximum pressure from 180mmHg to 140mmHg and the addition of a sleeve type. The sponsor asserts equivalence to the LF400 (K150033), which also has a maximum pressure of 140mmHg.

1. A table of acceptance criteria and the reported device performance

Since this is not a diagnostic device, the acceptance criteria are not presented in terms of diagnostic metrics (e.g., sensitivity, specificity). Instead, they are related to safety, electromagnetic compatibility, and basic product performance after the pressure change.

Acceptance Criterion (Addressed by)	Reported Device Performance
Electrical Safety	Complied with IEC 60601-1:2012
Electromagnetic Compatibility	Complied with IEC 60601-1-2:2014
Product Performance (Pressure)	Performance testing conducted to verify functionality with changed maximum pressure of 140mmHg.
Product Performance (Sleeve Compatibility)	Compatibility testing with added sleeve types.
Biocompatibility	Not verified by FDA; device not intended for direct skin contact (requires use over clothing/socks).

2. Sample size used for the test set and the data provenance

Sample Size: Not applicable. The "test set" for this device consists of non-clinical retests and gap tests of the device itself, not patient data.
Data Provenance: The tests conducted are in-house tests ("Inhouse test] Product Performance Test report, RND-R-PRR-103-02(2022.06.13)"). This indicates the testing was performed by the manufacturer. Specific country of origin for the testing is not detailed beyond the manufacturer's location (Republic of Korea).

3. Number of experts used to establish the ground truth for the test set and the qualifications of those experts

Not applicable. This device is not an AI/ML or diagnostic device requiring expert interpretation for ground truth. Its performance is assessed through objective engineering and safety standards.

4. Adjudication method (e.g., 2+1, 3+1, none) for the test set

Not applicable. Adjudication methods are used for subjective interpretations in diagnostic studies, which is not relevant here. Compliance with safety and performance standards is objective.

5. 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

Not applicable. This device is an intermittent pneumatic compression system and does not involve AI or human "readers."

6. If a standalone (i.e. algorithm only without human-in-the loop performance) was done

Not applicable. This device does not contain an algorithm in the sense of AI/ML. Its performance is assessed as a standalone electromechanical device. Clinical testing was not required to demonstrate substantial equivalence.

7. The type of ground truth used (expert consensus, pathology, outcomes data, etc.)

Not applicable in the context of diagnostic accuracy. The "ground truth" for this device's performance would be the objective measurements obtained during electrical safety, electromagnetic compatibility, and product performance testing against specified engineering limits and standards.

8. The sample size for the training set

Not applicable. This device does not involve a training set as it is not an AI/ML algorithm.

9. How the ground truth for the training set was established

Not applicable, as there is no training set for this device.

Summary

FDA 510(k) Clearance Letter - LF900 Powered Inflatable Tube Massager

Page 1

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

Doc ID # 04017.06.03

July 19, 2023

Daesung Maref Co., Ltd
Su Hyeon So
Jr. RA Specialist
298-24, Gongdan-ro
Gunpo-Si, Gyeonggido 15809
Korea, South

Re: K231437
Trade/Device Name: LF900
Regulation Number: 21 CFR 890.5650
Regulation Name: Powered Inflatable Tube Massager
Regulatory Class: Class II
Product Code: IRP
Dated: June 2, 2023
Received: June 22, 2023

Dear Su Hyeon So:

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 statutes and regulations administered by other Federal agencies. You must comply with all the Act's

Page 2

K231437 - Su Hyeon So
Page 2

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) 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-reporting-combination-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-devices/medical-device-safety/medical-device-reporting-mdr-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/medical-devices/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-devices/device-advice-comprehensive-regulatory-assistance/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,

Julia E. Slocomb -S 2023.07.19 07:58:39 -04'00'

for 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

Page 3

DEPARTMENT OF HEALTH AND HUMAN SERVICES	Form Approved: OMB No. 0910-0120
Food and Drug Administration	Expiration Date: 06/30/2023

Indications for Use

See PRA Statement below.

510(k) Number (if known)
K231437

Device Name
LF900

Indications for Use (Describe)
LF900 is intended for use by medical professionals and patients at home, who are under medical supervision, in treating many conditions, such as: Primary lymphedema, Edema following trauma and sport injuries, Postimmobilization edema, venous insufficiencies, Lymphedema.

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)

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
PRAStaff@fda.hhs.gov

"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."

FORM FDA 3881 (6/20)
Page 1 of 1

Page 4

510(k) Summary

K231437

1. Data Prepared [21 CFR 807.92(a)(a)]

May 10, 2023

2. Submitter's Information [21 CFR 807.92(a)(1)]

Name of Manufacturer: DAESUNG MAREF CO., LTD.
Address: 298-24, Gongdan-ro Gunpo-si, Gyeonggido Republic of Korea
Contact Name: Su Hyeon, So
Telephone No.: 82-31-459-7211
Fax No.: 82-31-459-7215
Email Address: rndra@dsmaref.com
Registration No.: 3004116008

3. Trade Name, Regulation Name, Classification [21 CFR 807.92(a)(2)]

Trade / Device Name	LF900
Regulation Number	21 CFR 890.5650
Regulation Name	Massager, Powered Inflatable Tube
Regulation Class	II
Product Code	IRP

4. Description of the Device [21 CFR 807.92(a)(4), (a)(5)]

Operation Principle

Indication For Use

1 / 5

Page 5

510(k) Summary

K231437

1. Data Prepared [21 CFR 807.92(a)(a)]

May 10, 2023

2. Submitter's Information [21 CFR 807.92(a)(1)]

Name of Manufacturer: DAESUNG MAREF CO., LTD.
Address: 298-24, Gongdan-ro Gunpo-si, Gyeonggido Republic of Korea
Contact Name: Su Hyeon, So
Telephone No.: 82-31-459-7211
Fax No.: 82-31-459-7215
Email Address: rndra@dsmaref.com
Registration No.: 3004116008

3. Trade Name, Regulation Name, Classification [21 CFR 807.92(a)(2)]

Trade / Device Name	LF900
Regulation Number	21 CFR 890.5650
Regulation Name	Massager, Powered Inflatable Tube
Regulation Class	II
Product Code	IRP

4. Description of the Device [21 CFR 807.92(a)(4), (a)(5)]

Operation Principle	This product is an Intermittent Pneumatic Compression system to improve the blood circulation of the human body. The operating principle is that the air from the device will be delivered to the sleeve with 4 air chambers and the air pressurizes sequentially the chambers from 1st to 4th.
Indication For Use	LF900 is intended for use by medical professionals and patients at home, who are under medical supervision, in treating many conditions, such as: Primary lymphedema, Edema following trauma and sport injuries, Postimmobilization edema, Venous insufficiencies, Lymphedema.

1 / 5

Page 6

5. Identification of Predicate Device(s) [21 CFR 807.92(a)(3)]

Predicate Device

510(k) Number: K150033
Applicant: DAESUNG MAREF CO., LTD.
Trade / Device Name: LF400
Regulation Number: 21 CFR 890.5650
Regulation Name: Massager, Powered Inflatable Tube
Regulation Class: II
Product Code: IRP
Indication For Use: LF-400 is intended for use by medical professionals and patients at home, who are under medical supervision, in treating many conditions, such as: Primary lymphedema, Edema following trauma and sport injuries, Postimmobilization edema, Venous insufficiencies, Lymphedema.

*Predicate device has not been subject to a design-related recall.

Reference Device

510(k) Number: K203019
Applicant: DAESUNG MAREF CO., LTD.
Trade / Device Name: LF900
Regulation Number: 21 CFR 890.5650
Regulation Name: Massager, Powered Inflatable Tube
Regulation Class: II
Product Code: IRP
Indication For Use: LF900 is intended for use by medical professionals and patients at home, who are under medical supervision, in treating many conditions, such as: Primary lymphedema, Edema following trauma and sport injuries, Postimmobilization edema, Venous insufficiencies, Lymphedema.

2 / 5

Page 7

5. Identification of Predicate Device(s) [21 CFR 807.92(a)(3)]

Predicate Device

510(k) Number: K150033
Applicant: DAESUNG MAREF CO., LTD.
Trade / Device Name: LF400
Regulation Number: 21 CFR 890.5650
Regulation Name: Massager, Powered Inflatable Tube
Regulation Class: II
Product Code: IRP
Indication For Use: LF-400 is intended for use by medical professionals and patients at home, who are under medical supervision, in treating many conditions, such as: Primary lymphedema, Edema following trauma and sport injuries, Postimmobilization edema, Venous insufficiencies, Lymphedema.

*Predicate device has not been subject to a design-related recall.

Reference Device

510(k) Number: K203019
Applicant: DAESUNG MAREF CO., LTD.
Trade / Device Name: LF900
Regulation Number: 21 CFR 890.5650
Regulation Name: Massager, Powered Inflatable Tube
Regulation Class: II
Product Code: IRP
Indication For Use: LF900 is intended for use by medical professionals and patients at home, who are under medical supervision, in treating many conditions, such as: Primary lymphedema, Edema following trauma and sport injuries, Postimmobilization edema, Venous insufficiencies, Lymphedema.

2 / 5

Page 8

6. Determination of Substantial Equivalence

Summary of technological characteristics of the device compared to the predicate device. [21CFR 807.92(a)(6)]

The pressure of the previously approved LF900 (K203019) has been changed from 180mmHg to 140mmHg, and a sleeve type has been added.

Through the table 1 below, we assert that the modified LF900 (K231437) is substantially equivalent to the LF400 (K150033).

[Table 1. Comparison of Proposed Device to Predicate Device]

	Proposed Device	Predicate Device	Reference Device
Model Name	LF900	LF400	LF900
510(k) Number	K231437	K150033	K203019
Manufacturer	DAESUNG MAREF CO., LTD.	DAESUNG MAREF CO., LTD.	DAESUNG MAREF CO., LTD.
Product Code	IRP	IRP	IRP
Device Class	II	II	II
Regulation Number	21 CFR 890.5650	21 CFR 890.5650	21 CFR 890.5650
Regulation Name	Massager, Powered Inflatable Tube	Massager, Powered Inflatable Tube	Massager, Powered Inflatable Tube
Indications For Use	LF900 is intended for use by medical professionals and patients at home, who are under medical supervision, in treating many conditions, such as: Primary lymphedema, Edema following trauma and sport injuries, Postimmobilization edema, Venous insufficiencies, Lymphedema.	LF-400 is intended for use by medical professionals and patients at home, who are under medical supervision, in treating many conditions, such as: Primary lymphedema, Edema following trauma and sport injuries, Postimmobilization edema, Venous insufficiencies, Lymphedema.	LF900 is intended for use by medical professionals and patients at home, who are under medical supervision, in treating many conditions, such as: Primary lymphedema, Edema following trauma and sport injuries, Postimmobilization edema, Venous insufficiencies, Lymphedema.
Intended Use environment	Professional healthcare environment & Home environment	Professional healthcare environment & Home environment	Professional healthcare environment & Home environment

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Page 9

	Proposed Device	Predicate Device	Reference Device
Specifications	Leg SleeveArm SleeveExtension zipperOne touch Single tubingOne touch Double tubing	Leg SleeveArm SleeveExtension zipperOne touch Single tubingOne touch Double tubing	Leg SleeveExtension zipperOne touch Single tubingOne touch Double tubing

Specifications

	Proposed Device	Predicate Device	Reference Device
Power Source	100-127V~, 50/60Hz	100-127V~, 50/60Hz	100-127V~, 50/60Hz
Time	5-90 min	5~180min	5-90 min
Pressure	10-140mmHg	20~140mmHg	10-180mmHg
Number of chamber	4	4	4

[Table 2. Little difference with Predicate Device]

Justification to Support Substantial Equivalence

The pressure of the LF900 was changed to be the same as that of the LF400 to add the arm sleeves used for the LF400. LF900 and LF400 have the same principle of operation and intended use, and the pressure is the same, so it is judged that the two products are substantial equivalent.

Non-Clinical Test Summary

According to the pressure change of LF900, retests and gap tests related to electrical safety and electromagnetic compatibility were performed, and the standards recognized by the FDA were complied with.

The following data were provided in support of the substantial equivalence determination:

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Page 10

1) Electrical Safety, Electromagnetic Compatibility and Performance

The proposed device (LF900) complied with the following standards for the electrical safety and electromagnetic compatibility requirements of the product after the changed maximum pressure and firmware was changed.

IEC 60601 : 2005/A1:2012, Medical Electrical Equipment: Part 1: General Requirements for Basic Safety and Essential Performance
IEC 60601 60601-1-2:2014, Medical Electrical Equipment - Part 1 1-2: General Requirements for Basic Safety and Essential Performance - Collateral Standard: Electromagnetic Disturbances -Requirements and Tests

[Inhouse test] Product Performance Test report, RND-R-PRR-103-02(2022.06.13)
Product performance test according to pressure change of LF900 and compatibility test with the sleeve to be added.

Clinical Test Summary

Clinical testing was not required to demonstrate the substantial equivalence of the LF900 to its predicate device

The device should only be used over full clothing and socks (because the cuffs cover the feet), never on direct skin.

The biocompatibility of the materials has not been verified by the FDA and contact of the cuffs/accessories to direct skin may lead to skin irritation, skin sensitization and/or cytotoxicity.

7. Conclusion [21 CFR 807.92(b)(3)]

The LF900 have similar intended use and technical characteristics to the predicate device. Based on that information, we conclude that the differences between the proposed device (LF900) and predicate device (LF400) do not introduce a new intended use and do not raise new issues of safety and effectiveness.

5 / 5

Regulation Number and Section

§ 890.5650 Powered inflatable tube massager.

(a)
Identification. A powered inflatable tube massager is a powered device intended for medical purposes, such as to relieve minor muscle aches and pains and to increase circulation. It simulates kneading and stroking of tissues with the hands by use of an inflatable pressure cuff.(b)
Classification. Class II (performance standards).