BTL-899TT

K252963 · BTL Industries, Inc. · IMJ · Jun 12, 2026 · Physical Medicine

Device Facts

• Record ID: K252963
• Device Name: BTL-899TT
• Applicant: BTL Industries, Inc.
• Product Code: IMJ · Physical Medicine
• Decision Date: Jun 12, 2026
• Decision: SESE
• Submission Type: Traditional
• Regulation: 21 CFR 890.5290
• Device Class: Class 2
• Attributes: Therapeutic

Indications for Use

BTL-899TT is indicated to be used in applying therapeutic deep heat in body tissues for the treatment of selected medical conditions such as disorders of the musculoskeletal system, muscle spasm, joint stiffness, contractures, and chronic inflammatory or infective conditions such as tenosynovitis, bursitis, synovitis and chronic inflammatory pelvic diseases.

Device Story

BTL-899TT is a non-invasive shortwave diathermy device for professional use in healthcare facilities; delivers 27.12 MHz radiofrequency (RF) energy via capacitive applicators to induce therapeutic deep heat (40-43°C) in body tissues. System comprises a main console with a 15.6-inch color touch-screen and multiple applicators; enables hands-free operation. User interface guides clinicians through therapy setup and monitors parameters. Integrated surface temperature sensor ensures tissue does not exceed 43°C. Output intensity is adjustable (0-100%). Device provides localized heating to treat muscle spasms, joint stiffness, and chronic inflammatory conditions; benefits include pain relief and increased local blood flow. Clinicians operate the device to manage therapy duration and intensity based on patient needs.

Clinical Evidence

No clinical data. Bench testing only. Thermal characterization confirmed the device maintains 40-43°C in tissue-mimicking material. Electrical safety, biocompatibility (ISO 10993-1, 5, 10), and electromagnetic compatibility (IEC 60601-1-2) verified.

Technological Characteristics

Shortwave diathermy (21 CFR 890.5290). Energy source: 100-240V AC. RF frequency: 27.12 MHz. Capacitive energy transfer. Max power: 30W per applicator. Features: 15.6-inch color touch-screen, surface temperature sensor. Standards: IEC 60601-1, IEC 60601-1-2, IEC 62304, ISO 14971, ISO 10993. Sterilization: Not specified.

Indications for Use

Indicated for patients requiring therapeutic deep heat for musculoskeletal disorders, muscle spasm, joint stiffness, contractures, and chronic inflammatory/infective conditions including tenosynovitis, bursitis, synovitis, and chronic inflammatory pelvic disease.

Regulatory Classification

Identification

A nonthermal shortwave therapy is a prescription device that applies to the body pulsed electromagnetic energy in the RF bands of 13.56 MHz or 27.12 MHz and that is intended for adjunctive use in the palliative treatment of postoperative pain and edema of soft tissue by means other than the generation of deep heat within body tissues as described in paragraph (a) of this section.

Special Controls

*Classification: Class II (special controls).* The device is classified as class II. The special controls for this device are:(i) Components of the device that come into human contact must be demonstrated to be biocompatible. (ii) Appropriate analysis/testing must demonstrate that the device is electrically safe and electromagnetically compatible in its intended use environment. (iii) Non-clinical performance testing must demonstrate that the device performs as intended under anticipated conditions of use. Non-clinical performance testing must characterize the output waveform of the device and demonstrate that the device meets appropriate output performance specifications. The output characteristics and the methods used to determine these characteristics, including the following, must be determined: (A) Peak output power; (B) Pulse width; (C) Pulse frequency; (D) Duty cycle; (E) Characteristics of other types of modulation that may be used; (F) Average measured output powered into the RF antenna/applicator; (G) Specific absorption rates in saline gel test load or other appropriate model; (H) Characterization of the electrical and magnetic fields in saline gel test load or other appropriate model for each RF antenna and prescribed RF antenna orientation/position; and (I) Characterization of the deposited energy density in saline gel test load or other appropriate model. (iv) A detailed summary of the clinical testing pertinent to use of the device to demonstrate the effectiveness of the device in its intended use. (v) Labeling must include the following: (A) Output characteristics of the device; (B) Recommended treatment regimes, including duration of use; and (C) A detailed summary of the clinical testing pertinent to the use of the device and a summary of the adverse events and complications. (vi) Nonthermal shortwave therapy devices marketed prior to the effective date of this reclassification must submit an amendment to their previously cleared premarket notification (510(k)) demonstrating compliance with these special controls.

Predicate Devices

• ThermoPro (K161862)

Submission Summary (Full Text)

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**FDA** **U.S. FOOD & DRUG**
ADMINISTRATION

June 12, 2026

BTL Industries, Inc.
David Chmel
CEO North America
362 Elm Street
Marlborough, Massachusetts 01752

Re: K252963

Trade/Device Name: BTL-899TT
Regulation Number: 21 CFR 890.5290
Regulation Name: Shortwave Diathermy
Regulatory Class: Class II
Product Code: IMJ
Dated: September 15, 2025
Received: September 17, 2025

Dear David Chmel:

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 (the 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 available 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.

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

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K252963 - David Chmel

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Additional information about changes that may require a new premarket notification are provided in the FDA guidance documents entitled "Deciding When to Submit a 510(k) for a Change to an Existing Device" (https://www.fda.gov/media/99812/download) and "Deciding When to Submit a 510(k) for a Software Change to an Existing Device" (https://www.fda.gov/media/99785/download).

Your device is also subject to, among other requirements, the Quality Management System Regulation (QMSR) (21 CFR Part 820), which includes, but is not limited to, ISO 13485 clause 7.3 (Design controls), ISO 13485 clause 8.3 (Nonconforming product), ISO 13485 clause 8.5.2 (Corrective action), and ISO 13485 clause 8.5.3 (Preventative action). Please note that regardless of whether a change requires premarket review, the QMSR requires device manufacturers to review and approve changes to device design and production (ISO 13485 clause 7.3 and ISO 13485 clause 7.5) and document changes and approvals in the Medical Device File (ISO 13485 clause 4.2.3).

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 Part 803) for devices or postmarketing safety reporting (21 CFR Part 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 Management System Regulation (QMSR) (21 CFR Part 820) for devices or current good manufacturing practices (21 CFR Part 4, Subpart A) for combination products; and, if applicable, the electronic product radiation control provisions (Sections 531-542 of the Act); 21 CFR Parts 1000-1050.

All medical devices, including Class I and unclassified devices and combination product device constituent parts are required to be in compliance with the final Unique Device Identification System rule ("UDI Rule"). The UDI Rule requires, among other things, that a device bear a unique device identifier (UDI) on its label and package (21 CFR 801.20(a)) unless an exception or alternative applies (21 CFR 801.20(b)) and that the dates on the device label be formatted in accordance with 21 CFR 801.18. The UDI Rule (21 CFR 830.300(a) and 830.320(b)) also requires that certain information be submitted to the Global Unique Device Identification Database (GUDID) (21 CFR Part 830 Subpart E). For additional information on these requirements, please see the UDI System webpage at https://www.fda.gov/medical-devices/device-advice-comprehensive-regulatory-assistance/unique-device-identification-system-udi-system.

Also, please note the regulation entitled, "Misbranding by reference to premarket notification" (21 CFR 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-

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assistance/contact-us-division-industry-and-consumer-education-dice) for more information or contact DICE by email ([e-mail]) or phone [phone] or 301-796-7100).

Sincerely,

AMBER T. BALLARD -S

Amber Ballard, PhD

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

Enclosure

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DEPARTMENT OF HEALTH AND HUMAN SERVICES
Food and Drug Administration

Form Approved: OMB No. 0910-0120
Expiration Date: 07/31/2026
See PRA Statement below.

# Indications for Use

510(k) Number (if known)
K252963

Device Name

BTL-899TT

Indications for Use (Describe)

BTL-899TT is indicated to be used in applying therapeutic deep heat in body tissues for the treatment of selected medical conditions such as disorders of the musculoskeletal system, muscle spasm, joint stiffness, contractures, and chronic inflammatory or infective conditions such as tenosynovitis, bursitis, synovitis and chronic inflammatory pelvic diseases.

Generally accepted indications for use:

- o Pain Relief
- o Contractures
- o Reduce Muscle Spasm
- o Localized increase Blood Flow
- o Chronic Inflammatory Conditions
- o Bursitis
- o Decrease Joint Stiffness
- o Tenosynovitis
- o Synovitis
- o Chronic Inflammatory Pelvic Disease

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.

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BTL Industries

## 510(k) Summary
K252963

General Information

Sponsor: BTL Industries, Inc.
362 Elm Street
Marlborough, MA 01752
Tel: [phone]
Fax: [phone]

Applicant: BTL Industries, Inc.
362 Elm Street
Marlborough, MA 01752
Tel: [phone]
Fax: [phone]

Contact Person: David Chmel
BTL Industries, Inc.
[e-mail]

Summary Preparation
Date: 10 June 2026

Device Name

Trade/Proprietary Name: BTL-899TT
Common Name: Diathermy, Shortwave,
For Use In Applying Therapeutic Deep Heat
Regulation Number: 21 CFR 890.5290
Classification Name: Shortwave diathermy
Regulatory Class: Class II
Product Code: IMJ

510(k) Summary
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# Legally Marketed Predicate Device

The BTL-899TT uses radiofrequency energy for the therapeutic application of deep heat and is substantially equivalent to the current product that is already cleared for distribution in the USA under the following 510(k) Premarket Notification number:

# Predicate device:

Device name: ThermoPro

Original 510(k) Sponsor: Zimmer MedizinSysteme GmbH

510(k) Number: K161862

# Device Description

The BTL-899TT is a non-invasive therapeutic device consisting of a main unit and applicators (899-AP-C-1, 899-AP-C-2, 899-AP-C-4 and 899-AP-C-5) designed to deliver electromagnetic energy of 27.12 MHz to targeted tissues. The device is intended for use in applying therapeutic deep heat to body tissues for the treatment of selected medical conditions such as disorders of the musculoskeletal system, muscle spasm, joint stiffness, contractures, and chronic inflammatory or infective conditions such as tenosynovitis, bursitis, synovitis and chronic inflammatory pelvic diseases. The device enables hands-free operation. When therapy is applied, the patient should experience a pleasant warming sensation in the treatment area. The device is intended solely for professional use in healthcare facilities. The device is designed for indoor use only. The device is not intended for home-use.

The BTL-899TT is equipped with a large color touch-screen that facilitates the use of the device. The on-screen information guides the user step-by-step through the entire therapy procedure. The therapeutic parameters are set using the touch screen of the device. During the therapy, the device displays information about the applied therapy type, remaining therapy time and main therapy parameters on the screen.

# Indications for Use

BTL-899TT is indicated to be used in applying therapeutic deep heat in body tissues for the treatment of selected medical conditions such as disorders of the musculoskeletal system, muscle spasm, joint stiffness, contractures, and chronic inflammatory or infective conditions such as tenosynovitis, bursitis, synovitis and chronic inflammatory pelvic diseases.

Generally accepted indications for use:

- o Pain Relief
- o Contractures
- o Reduce Muscle Spasm
- o Localized increase Blood Flow
- o Chronic Inflammatory Conditions
- o Bursitis
- o Decrease Joint Stiffness
- o Tenosynovitis

510(k) Summary
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BTL Industries

o Synovitis
o Chronic Inflammatory Pelvic Disease

### Non-clinical Testing (Performance, Bench Testing)

The BTL-899TT device has been thoroughly evaluated for electrical safety, biocompatibility, electromagnetic compatibility, software, and performance. The device has been found to comply with the following applicable medical device safety standards:

| IEC 60601-1 | Medical electrical equipment – Part 1: General requirements for basic safety and essential performance |
| --- | --- |
| IEC 60601-1-2 | Medical electrical equipment – Part 1-2: General requirements for basic safety and essential performance - Collateral standard: Electromagnetic compatibility – Requirements and tests |
| IEC 62304 | Medical device software – Software life cycle processes |
| ISO 14971 | Medical devices – Application of risk management to medical devices |
| ISO 10993-1 | Biological evaluation of medical devices – Part 1: Evaluation and testing within a risk management process |
| ISO 10993-5 | Biological evaluation of medical devices – Part 5: Tests for in vitro cytotoxicity |
| ISO 10993-10 | Biological evaluation of medical devices – Part 10: Tests for irritation and skin sensitization |

Thermal characterization testing to demonstrate that the device can maintain temperature in the range of approx. 40-43°C using a tissue-mimicking material was conducted. The results of this evaluation confirmed the ability of the BTL-899TT device to maintain therapeutic heating levels for the duration of therapy and that the surface temperature sensor ensures that the body surface temperature does not exceed 43°C (±1°C).

### Clinical Testing

Not applicable

### Technological Characteristics

The BTL-899TT device has the same intended use and comparable technological characteristics and principles of operation to its predicate device. The BTL-899TT device and its predicate are comprised of a system console and applicator(s). The system console consists of the generators, computer, and the touch-screen control panel.

The technological similarities and differences between the BTL-899TT device and the predicate device are presented below in the comparison table. The differences do not raise any increased safety or effectiveness concerns compared to the predicate device.

510(k) Summary

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**BTL Industries**

# **Comparison with the Predicate Device**

| 510(k) number Device name | K252963 BTL-899TT | K161862 ThermoPro | Similarities/ Difference |
| --- | --- | --- | --- |
| Company name | BTL Industries, Inc. | Zimmer MedizinSysteme GmbH | |
| | Subject device | Predicate device | |
| Product Code and Regulation | Physical Medicine 21 CFR 890.5290 IMJ – Diathermy, Shortwave, for use in applying therapeutic deep heat | Physical Medicine 21 CFR 890.5290 IMJ – Diathermy, Shortwave, for use in applying therapeutic deep heat | **Same** |
| Indications for Use | BTL-899TT is indicated to be used in applying therapeutic deep heat in body tissues for the treatment of selected medical conditions such as disorders of the musculoskeletal system, muscle spasm, joint stiffness, contractures, and chronic inflammatory or infective conditions such as tenosynovitis, bursitis, synovitis and chronic inflammatory pelvic diseases. Generally accepted indications for use: o Pain Relief o Contractures o Reduce Muscle Spasm o Localized increase Blood Flow o Chronic Inflammatory Conditions o Bursitis o Decrease Joint Stiffness o Tenosynovitis o Synovitis o Chronic Inflammatory Pelvic Disease | Indications for use in applying therapeutic deep heat in body tissues for the treatment of selected medical conditions such as disorders of the musculoskeletal system, muscle spasm, joint stiffness, contractures, and chronic inflammatory or infective conditions such as tenosynovitis, bursitis, synovitis and chronic inflammatory pelvic diseases. Generally accepted indications for use: • Pain Relief • Contractures • Reduce Muscle Spasm • Localized increase Blood Flow • Chronic Inflammatory Conditions • Bursitis • Decrease Joint Stiffness • Tenosynovitis • Synovitis • Chronic Inflammatory Pelvic Disease. | **Same** |
| Electrical Protection | Class II, BF | Class I, BF | **Same** |
| Clinical Use | Prescription use | Prescription use | **Same** |

510(k) Summary
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**BTL Industries**

| Interface | Touch screen | Touch screen | Same |
| --- | --- | --- | --- |
| **Type of Energy** | Deep heating of tissue by therapeutic application of radio frequency electrical currents | Deep heating of tissue by therapeutic application of radio frequency electrical currents | **Same** |
| **Color Touch Screen** | 15.6 in 1920 x 1080 px. | Not publicly available | The difference in display size and resolution represents a modification to the user interface and has no direct impact on the therapeutic effect of the device. |
| **Type of operation** | Continuous | Continuous and Pulsed | Both devices heat the target tissue to a therapeutic temperature range; from a safety perspective, the device is capable of regulating its output to prevent the target tissue from overheating beyond the required temperature range, as confirmed by performance bench testing. This difference does not raise increased concerns regarding safety or efficacy. |
| **Output intensity** | 0–100 % | Not publicly available | The representation of output intensity in relative values (0–100%) is a standard approach to user power settings and is one of the possible ways to indicate a device's output intensity. This difference does not impact safety or efficacy. |
| **RF Type** | Capacitive | Not publicly available | The subject device utilizes a capacitive type of radiofrequency energy transfer, which is one of the established methods for shortwave diathermy to heat tissue. The lower maximum power of the subject device does not affect its ability to reach the therapeutic temperature range, as verified through performance bench testing. |
| **Max. RF Power @50Ohm** | 30W per applicator (2x) | Output Power: 100W Pulsed Output Power: 200W | |
| **RF Frequency** | 27.12 Mhz | 27.12 Mhz | **Same** |
| **Temperature Sensor** | Yes | Not publicly available | The subject device is equipped with a temperature sensor that monitors the temperature on the patient's body surface at the application site. The functionality of the sensor was verified through software validation |

510(k) Summary
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**BTL Industries**

| | | | and the provided performance bench testing. This difference does not raise increased safety concerns compared to the predicate device. |
| --- | --- | --- | --- |
| **Therapy Time Displayed** | Up to 30 min Yes | Up to 30 min Yes | **Same** |
| **Favorites programs** | Yes | Yes | **Same** |
| **Energy Source** | 100 – 240 V AC, 50–60 Hz | 100 – 240 V AC, 50–60 Hz, | **Same** |
| **System Dimensions (W×H×D)** | 23 x 39 x 29 in (592 x 985 x 730 mm) | 33.64 h x 22.9 w x 18.0 d in (854 x 581 x 459 mm) | The differences in physical dimensions and weight between the subject device and the predicate device are due to the distinct designs of the two devices and have no impact on device safety or efficacy. |
| **System Weight** | 70 kg | 37 kg | |
| **Ambient Storage Temperature** | -10°C to +55°C | Not publicly available | **Similar** |
| **Relative Storage Humidity** | 10% to 85% | Not publicly available | **Similar** |
| **Environmental Specifications** | For indoor use only | Not publicly available | **Similar** |

510(k) Summary
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BTL Industries

## Substantial Equivalence Discussion

The technological differences between the subject device and the predicate device identified in the SE table below include the RF type, maximum output power, and physical parameters (weight, dimensions, and display size).

Although the devices differ in the used RF Type specifically, both devices operate at an identical frequency of 27.12 MHz. They both produce the same heating effect in the treated tissue, whether through dielectric losses or eddy currents, and result in comparable temperature rises to achieve therapeutic deep heating.

The difference in maximum output power does not affect the ability of the subject device to achieve the required thermal effect in the treated tissue, as the subject device, like the predicate device, is capable of reaching and maintaining the therapeutic deep heating range.

Therefore, these differences do not introduce any new or modified risks or concerns related to safety or effectiveness, and the subject device, BTL-899TT, has been shown to be substantially equivalent to the cleared predicate device.

## Conclusion

Based upon the intended use and the technical data provided in this pre-market notification, the BTL-899TT device is substantially equivalent to the K161682 predicate device.

---510(k) Summary
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