Introduction
This manual provides detailed instructions for the Docooler F520 Wireless Business Headset. Please read this manual carefully before use to ensure proper operation and to maximize the product's lifespan. Keep this manual for future reference.
The Docooler F520 is a versatile wireless headset designed for business, sport, and everyday use. It features Bluetooth 5.3 for stable connectivity, a retractable earbud for convenience, and a high-definition microphone with noise reduction for clear calls.
Package Contents
The Docooler F520 package includes:
- 1 x Docooler F520 Wireless Headset
- 1 x USB Charging Cable
- 2 x Silicone Ear Caps (various sizes)
- 1 x User Manual
Product Overview
The Docooler F520 headset is designed for comfort and functionality, featuring a collar clip design and a retractable earbud.

Image: Main view of the Docooler F520 Wireless Headset, showcasing its compact design and retractable earbud.

Image: Diagram illustrating the dimensions and key components of the F520 headset, including the button to retract earbud, LED indicator, Type-C USB port, volume buttons, and microphone.

Image: Detailed view highlighting the Type-C USB charging port, independent volume control buttons, and the three sizes of skin-friendly silicone ear caps (L, M, S) included for comfortable wear.
Setup
Charging the Headset
Before first use, fully charge the headset. Connect the provided USB charging cable to the Type-C port on the headset and to a compatible USB power source (e.g., computer USB port, wall adapter). The LED indicator will illuminate during charging and change color or turn off when fully charged (refer to specific LED behavior in the diagram).
- Charging Time: Approximately 2 hours.
- Battery Life: Up to 10 hours talk time, 14 hours music time (at 70% volume), 120 hours standby time.

Image: Diagram illustrating the impressive battery life of the F520 headset, showing 10 hours of talk time, 14 hours of music time, and 120 hours of standby time.
Bluetooth Pairing
The F520 headset utilizes advanced Bluetooth 5.3 technology for a stable, fast, and energy-efficient wireless connection.

Image: Visual representation of the Bluetooth 5.3 chip, emphasizing lower power consumption and smoother performance for enhanced wireless connectivity.
- Power On: Press and hold the Multi-function Button (MFB) for approximately 3 seconds until the LED indicator flashes, indicating the headset is in pairing mode.
- Enable Bluetooth: On your smartphone or other Bluetooth-enabled device, go to the Bluetooth settings and ensure Bluetooth is turned on.
- Search for Devices: Your device will automatically search for nearby Bluetooth devices.
- Connect: Select "F520" from the list of available devices. Once connected, the LED indicator will change (e.g., slow blue flash) and you will hear an audible confirmation.
Multi-point Connection: The F520 supports connecting to two smartphones simultaneously. After pairing with the first device, disable Bluetooth on the first device, then pair with the second device. Re-enable Bluetooth on the first device, and the headset should connect to both.
Operating Instructions
The F520 headset features intuitive physical buttons for easy control of calls, music, and voice assistant functions.

Image: Diagram illustrating the functions of the physical buttons on the F520 headset, including power, call control, music playback, volume adjustment, and voice assistant activation.
- Power On/Off:
Press and hold the Multi-function Button (MFB) for 3 seconds. - Answering/Ending Calls:
Click the MFB once. - Rejecting Calls:
Double-click the MFB. - Redial Last Number:
Double-click the MFB. - Play/Pause Music:
Click the MFB once. - Switch Song:
Long press the Volume + button for 2 seconds for the next song.
Long press the Volume - button for 2 seconds for the previous song. - Adjust Volume:
Click the Volume + button to increase volume.
Click the Volume - button to decrease volume. - Voice Assistant (Siri):
Long press the MFB for 2 seconds to activate your device's voice assistant. - Retract Earbud:
Press the dedicated button on the side of the headset to automatically retract the earbud cable, keeping it organized and tangle-free.
Call Quality and Noise Reduction
The F520 features a built-in high-definition microphone with multiple noise reduction technologies to enhance call audio transmission, ensuring clear sound and high-quality conversations.

Image: Diagram illustrating the intelligent noise reduction feature, showing how ambient noise is reduced for clearer voice calls. It also highlights effective wind noise reduction for speeds up to 60km/h.
Single-Ear Design for Safe Travel
The monaural design allows you to enjoy audio while remaining aware of your surroundings, which is beneficial for driving, riding, or general travel safety.

Image: A person wearing the F520 headset, demonstrating its single-ear design which allows for privacy while also maintaining environmental awareness, promoting safer travel.
Maintenance
Cleaning
Wipe the headset with a soft, dry, lint-free cloth. Do not use abrasive cleaners, solvents, or harsh chemicals. Avoid getting moisture into any openings.
Storage
Store the headset in a cool, dry place away from direct sunlight, extreme temperatures, and humidity. When not in use for extended periods, ensure the earbud cable is retracted to prevent damage.
Troubleshooting
- Headset won't turn on: Ensure the headset is fully charged. Connect it to a power source and try again after a few minutes.
- Cannot pair with device: Make sure Bluetooth is enabled on your device and the headset is in pairing mode (LED flashing). Try restarting both the headset and your device. Ensure the headset is not already connected to another device.
- No sound or low volume: Check the volume levels on both the headset and your connected device. Ensure the headset is properly paired and selected as the audio output device.
- Poor call quality: Ensure the microphone is not obstructed. Move closer to your connected device to ensure a strong Bluetooth signal. Avoid environments with strong electromagnetic interference.
- Earbud cable not retracting: Gently press the retraction button. If it's stuck, ensure there are no obstructions. Do not force the cable.
Specifications
| Feature | Detail |
|---|---|
| Brand | Docooler |
| Model Name | F520 |
| Model Number | LLS9325159902624XR |
| Material | ABS+PC+UV |
| Bluetooth Version | V5.3 |
| Battery Capacity | 80mAh |
| Music Playback Time | Approx. 14 hours (70% volume), 12 hours (100% volume) |
| Talk Time | Approx. 10 hours |
| Standby Time | Approx. 120 hours |
| Charging Time | Approx. 2 hours |
| Wire Length | Approx. 35 cm |
| Weight | 18.5g |
| Water Resistance | Waterproof |
| Control Method | Voice, Physical Buttons |
| Compatible Devices | Bluetooth-enabled devices |
| Ear Placement | In-ear |
| Form Factor | In-ear |
| Call Noise Reduction | Yes |
| Passive Noise Isolation | None |
| Connectivity Technology | Wireless (Bluetooth) |
| Specific Uses | Travel, Business, Sport |
Safety Information
- Do not disassemble, repair, or modify the headset. This may void the warranty and cause damage.
- Keep the headset away from extreme temperatures (hot or cold), direct sunlight, and high humidity.
- Avoid prolonged listening at high volumes to prevent potential hearing damage.
- Keep the device away from children and pets.
- Dispose of the product and its battery responsibly according to local regulations. Do not dispose of with household waste.
Warranty and Support
For warranty information, technical support, or any inquiries regarding your Docooler F520 Wireless Business Headset, please refer to the documentation provided at the time of purchase. You may also contact Docooler customer service through their official website or authorized retailers for assistance.



