1. Introduction
Thank you for choosing the CUGUU Mini 503 Bluetooth Headphone. This wireless stereo sport headset is designed for convenience and versatility, featuring Bluetooth connectivity, an integrated MP3 player with TF card support, and an FM radio function. It is ideal for various activities including running, climbing, and office use.

Image: The Mini 503 headphones are available in multiple colors and are designed for active use, fitting securely around the head.
2. Safety Information
- Do not expose the headphones to extreme temperatures or humidity.
- Avoid dropping or subjecting the headphones to strong impacts.
- Keep away from water and liquids, as the headphones are not waterproof.
- Do not attempt to disassemble or modify the headphones.
- Charge the headphones using a standard USB power source. Avoid overcharging to prevent battery damage.
- Listen at moderate volume levels to prevent hearing damage.
3. Package Contents
Please check the package for the following items:
- CUGUU Mini 503 Bluetooth Headphone
- USB Charging Cable
- User Manual (this document)
4. Product Overview
The Mini 503 features intuitive controls for easy operation.

Image: Detailed view of the headphone controls and ports.
Controls and Ports:
- Power Button: Turns the headphones on/off, answers/ends calls.
- Multi-Function Buttons: Play/Pause music, manage calls.
- Previous Track Button: Skips to the previous song.
- Next Track Button: Skips to the next song.
- Volume +: Increases volume.
- Volume -: Decreases volume.
- USB Charging Port: For charging the device.
- Card Slot: For inserting a Micro SD (TF) card for MP3 playback.
5. Setup
5.1 Charging the Headphones
- Locate the USB charging port on the headphone.
- Connect the provided USB charging cable to the headphone and a compatible USB power source (e.g., computer USB port, USB wall adapter).
- The charging time is approximately 2.5-3 hours.
- Once fully charged, disconnect the charging cable. Avoid overcharging to protect the battery.
5.2 Bluetooth Pairing
- Ensure the headphones are turned off.
- Press and hold the Power Button until the indicator light flashes, indicating pairing mode.
- On your Bluetooth-enabled device (smartphone, tablet, laptop), go to the Bluetooth settings and search for available devices.
- Select "Mini 503" (or similar name) from the list of devices.
- Once connected, the indicator light will change or stop flashing.

Image: The headphones are compatible with a wide range of Bluetooth devices.
5.3 TF Card Insertion
- Locate the TF card slot on the headphone.
- Gently insert a Micro SD (TF) card with your MP3 music files into the slot until it clicks into place.
- The headphones will automatically switch to MP3 playback mode if a card is detected.

Image: Inserting a TF card for MP3 music playback.
6. Operating Instructions
6.1 Power On/Off
- Power On: Press and hold the Power Button until the indicator light turns on.
- Power Off: Press and hold the Power Button until the indicator light turns off.
6.2 Music Playback
- Play/Pause: Press the Multi-Function Button once.
- Next Track: Press the Next Track Button once.
- Previous Track: Press the Previous Track Button once.
- Volume Up: Press the Volume + button.
- Volume Down: Press the Volume - button.
6.3 Call Management
- Answer Call: Press the Power Button once when a call comes in.
- End Call: Press the Power Button once during a call.
- Reject Call: Press and hold the Power Button for a few seconds when a call comes in.
6.4 FM Radio
- To switch to FM radio mode, press the appropriate mode button (if available, otherwise it might be integrated with the Multi-Function button or a long press).
- Use the Next Track and Previous Track buttons to scan for radio stations.
- Note: FM radio functionality depends on local signal strength. Ensure you are in an area with strong FM signal for optimal performance.

Image: The headphones feature a built-in FM radio function.
7. Maintenance
- Cleaning: Use a soft, dry cloth to clean the headphones. Do not use abrasive cleaners or solvents.
- Storage: Store the headphones in a cool, dry place away from direct sunlight and extreme temperatures.
- Battery Care: If not used for extended periods, charge the headphones at least once every three months to maintain battery health.
8. Troubleshooting
| Problem | Possible Solution |
|---|---|
| Headphones won't turn on. | Ensure the headphones are fully charged. Connect to a power source and try again. |
| Cannot pair with Bluetooth device. |
|
| No sound or low volume. |
|
| FM radio not working well. | FM mode may not work in all locations. Ensure you are in an area with a strong FM signal. |
| Battery drains quickly. | Ensure the headphones are fully charged. Avoid overcharging. Battery life can vary based on usage and volume levels. |
9. Specifications
| Feature | Detail |
|---|---|
| Brand Name | CUGUU |
| Model | Mini 503 |
| Material | ABS |
| Style | Headband (Wireless) |
| Communication | Wireless (Bluetooth) |
| Bluetooth Version | 4.2 |
| Transmission Frequency | 2.4GHz |
| Frequency Response Range | 20 - 24800Hz |
| Sensitivity | 100dB |
| Resistance | 38 Ω |
| Impedance Range | from 33 to 100 Ω |
| Driver Diameter | 25mm |
| Number Of Drivers | 2 |
| Vocalism Principle | Dynamic |
| Total Harmonic Distortion | 1% |
| With Microphone | Yes |
| Volume Control | Yes |
| Control Button | Yes |
| Active Noise-Cancellation | No |
| Waterproof | No |
| Support Memory Card | Yes (Micro SD / TF Card) |
| Charging Method | Cable (USB) |
| Charge Time | 2.5-3 Hours |
| Music Playback Time | Approx. 7 Hours |
| Call Time | Approx. 8 Hours |
| Standby Time | Approx. 80 Hours |
| Functions | Bluetooth, MP3 Player (TF Card), FM Radio, Handsfree Calling |

Image: Battery capacity details for standby, call, and music playback.
10. User Tips
- For optimal FM radio performance, ensure you are in an area with a strong signal. FM reception can vary by location.
- To maximize battery life, avoid overcharging the headphones. Disconnect the charging cable once the charging indicator shows a full charge.
- The headphones support real-time power display on iOS and Android systems, allowing you to monitor battery levels directly on your phone.

Image: Real-time battery display on a smartphone.
11. Warranty and Support
For any questions, technical support, or warranty claims, please contact the seller or retailer from whom you purchased the product. Keep your proof of purchase for warranty purposes.





