1. Introduction
The Prorelax TENS/EMS Duo Comfort Blackline is an advanced electro-stimulation device designed for both muscle stimulation (EMS) and pain relief (TENS). This compact and stylish black device offers two effective therapies in one unit, making it an ideal partner for active individuals seeking performance enhancement and relief from chronic pain.
As a Class IIa CE medical device, it provides a safe and effective way to stimulate, sculpt, and alleviate discomfort. With its dual-channel design, 8 pre-set programs, and adjustable intensity levels, the Duo Comfort Blackline allows for personalized treatment sessions anytime, anywhere.

Figure 1.1: The Prorelax TENS/EMS Duo Comfort Blackline device with connected electrode pads, showcasing its sleek black design and clear display.
2. Safety Information
Please read all instructions carefully before using the device. Failure to follow safety guidelines may result in injury or device malfunction.
- Do not use if you have a pacemaker, implanted defibrillator, or other implanted metallic or electronic devices.
- Do not use if you are pregnant or suspect you might be pregnant.
- Do not use on areas of skin that are broken, inflamed, or have open wounds.
- Do not use near the heart, on the head, over the carotid sinus nerves (front of neck), or over the eyes.
- Consult a healthcare professional before use if you have any pre-existing medical conditions, including but not limited to epilepsy, heart disease, or cancer.
- Keep out of reach of children.
- This device is for personal use only and should not be shared.
- Discontinue use immediately if you experience any adverse reactions or discomfort.
3. Package Contents
Upon opening your Prorelax TENS/EMS Duo Comfort Blackline package, please ensure all components are present and in good condition:
- Prorelax TENS/EMS Duo Comfort Blackline Device
- 4 Self-adhesive Electrode Pads (50x50mm)
- 2 Electrode Cables
- USB Charging Cable
- Power Adapter (for USB charging)
- Storage Case
- Instruction Manual (this document)

Figure 3.1: Overview of the complete Prorelax TENS/EMS Duo Comfort Blackline kit, including the device, electrode pads, cables, and charging accessories, all neatly arranged with a transparent protective cover and a storage case.
4. Setup
4.1 Charging the Device
The Prorelax TENS/EMS Duo Comfort Blackline features a built-in rechargeable Lithium-ion battery. Before first use, fully charge the device.
- Connect the USB charging cable to the device's charging port.
- Connect the other end of the USB cable to the provided power adapter or a compatible USB port (e.g., computer, car charger).
- The battery indicator on the display will show charging status. Once fully charged, the indicator will change.
4.2 Connecting Electrode Pads
The device has two independent channels (CH1 and CH2) for connecting electrode pads.
- Insert the pin connectors of the electrode cables into the corresponding ports on the top of the device (CH1 and CH2).
- Attach the electrode pads to the snap connectors at the end of the electrode cables. Ensure a secure connection.
4.3 Applying Electrode Pads
Proper placement of electrode pads is crucial for effective and safe treatment.
- Ensure the skin area where pads will be applied is clean, dry, and free of lotions or oils.
- Carefully peel the electrode pads from their protective film. Retain the film for storage.
- Apply the pads firmly to the desired treatment area. For TENS pain relief, place pads around the painful area. For EMS muscle stimulation, place pads on the muscle belly.
- Ensure pads are not touching each other.

Figure 4.1: Illustration of proper electrode pad application for both muscle stimulation and pain relief, highlighting ease of use and versatility for different body areas.

Figure 4.2: Example of electrode pad placement on the shoulder and chest for targeted stimulation or pain relief.
5. Operating Instructions
5.1 Power On/Off
- To turn on the device, press and hold the "ON +" button until the display illuminates.
- To turn off the device, press and hold the "OFF -" button until the display turns off.
5.2 Mode and Program Selection
The device offers 8 pre-set programs, combining TENS and EMS functionalities.
- After powering on, press the "MODE" button to cycle through the available programs (P1-P8).
- Each program has a specific waveform and frequency designed for different therapeutic effects (e.g., muscle strengthening, pain relief, massage). Refer to the program chart in the full manual for details on each program.
- The selected program number will be displayed on the screen.
5.3 Adjusting Intensity
The intensity can be adjusted independently for each channel (CH1 and CH2) across 25 levels.
- Press the "CH1" button to select Channel 1, then use "ON +" to increase intensity or "OFF -" to decrease intensity for Channel 1.
- Press the "CH2" button to select Channel 2, then use "ON +" to increase intensity or "OFF -" to decrease intensity for Channel 2.
- Adjust the intensity to a comfortable yet effective level. You should feel a strong, comfortable sensation, but no pain.
5.4 Setting the Timer
The device features a 12-level timer, allowing you to set the duration of your treatment session.
- While a program is selected, press the "MODE" button repeatedly until the timer setting is highlighted or accessible.
- Use the "ON +" and "OFF -" buttons to adjust the treatment duration. The display will show the remaining time in minutes.
- The device will automatically shut off once the set time has elapsed.

Figure 5.1: The Prorelax TENS/EMS Duo Comfort Blackline is suitable for active individuals, supporting muscle performance and aiding in recovery and pain relief after activities like running or tennis.

Figure 5.2: The device can be integrated into a fitness routine to optimize muscle performance and recovery, promoting a 'Fit for Life' lifestyle.
6. Maintenance
6.1 Cleaning the Device
- Always turn off and disconnect the device before cleaning.
- Wipe the device with a soft, damp cloth. Do not use abrasive cleaners or immerse the device in water.
- Ensure the device is completely dry before storing or next use.
6.2 Caring for Electrode Pads
The self-adhesive electrode pads are reusable but their lifespan depends on proper care.
- After each use, gently peel the pads from your skin.
- Place the pads back onto their protective film to prevent them from drying out and to maintain their adhesive quality.
- If the pads lose their stickiness, gently wipe the adhesive surface with a damp cloth (water only) and let them air dry. Do not use soap or alcohol.
- Replace pads when they no longer adhere well to the skin, as poor adhesion can lead to reduced effectiveness or skin irritation.

Figure 6.1: Original Prorelax Blackline 50x50mm electrode pads, available as replacements to ensure continued optimal performance of your device.
6.3 Storage
- Store the device and accessories in the provided storage case in a cool, dry place, away from direct sunlight and extreme temperatures.
7. Troubleshooting
If you encounter issues with your Prorelax TENS/EMS Duo Comfort Blackline, please refer to the following common problems and solutions:
| Problem | Possible Cause | Solution |
|---|---|---|
| Device does not turn on. | Low battery or device not charged. | Charge the device fully using the provided USB cable and power adapter. |
| No sensation or weak sensation. |
|
|
| Sensation is uncomfortable or stinging. |
|
|
| Display is not working correctly. | Device malfunction or low battery. | Try charging the device. If the problem persists, contact customer support. |
If the problem persists after trying these solutions, please contact Prorelax customer support for further assistance.
8. Technical Specifications
| Feature | Detail |
|---|---|
| Product Name | Duo Comfort Blackline Electric Muscle Stimulator with EMS + TENS |
| Model Number | 49702 |
| Brand | Prorelax |
| Device Type | TENS/EMS Electro-stimulation Device |
| Channels | 2 (independent) |
| Programs | 8 pre-set programs |
| Intensity Levels | 25 levels |
| Timer | 12-level adjustable timer |
| Power Source | Built-in Lithium-ion battery (rechargeable via USB) |
| Dimensions (L x W x H) | 5 x 1.5 x 12.5 cm (approx. 1.97 x 0.59 x 4.92 inches) |
| Weight | 60 grams (approx. 2.12 ounces) |
| Medical Device Class | Class IIa CE |
| Manufacturer | Euromedics |
| Country of Origin | Taiwan |
9. Warranty and Support
Prorelax products are manufactured to high-quality standards. For information regarding warranty coverage, please refer to the warranty card included in your product packaging or visit the official Prorelax website.
For technical support, troubleshooting assistance beyond this manual, or to inquire about replacement parts (such as electrode pads), please contact Prorelax customer service. Contact details can typically be found on the manufacturer's website or on the product packaging.
Note: Only use original Prorelax replacement parts and accessories to ensure optimal performance and safety of your device.





