Introduction
The ROCKBROS Electric Bike Horn is designed to enhance safety for cyclists by providing a loud and clear warning sound. This compact and waterproof electronic horn is suitable for various types of bicycles, including road bikes, mountain bikes, e-bikes, dirt bikes, folding bikes, kids' bikes, and scooters. It features a 120dB sound output and a simple one-button operation for ease of use.

Image: The ROCKBROS Electric Bike Horn highlighting its key features: 120dB loud sound, single warning tone, IPX4 waterproof rating, and long battery life.
Product Features
- 120dB Loud Sound: Emits a powerful 120dB sound to effectively alert pedestrians and other road users.
- IPX4 Waterproof: Designed to withstand light rain, making it suitable for daily riding in various weather conditions. Avoid prolonged exposure to heavy rain.
- Compact & Portable: Weighing only 34g, its small size minimizes handlebar space usage.
- Easy Installation: Features an elastic rubber strap for quick and tool-free mounting on handlebars of different diameters (22.2mm to 31.8mm).
- Replaceable Battery: Powered by a CR2032 battery, which can be replaced when needed, ensuring continuous functionality.
- Minimalist Design: Simple one-button operation for immediate sound activation.
What's in the Box
- 1 x ROCKBROS Electric Bike Horn
- 1 x Elastic Rubber Strap (pre-installed or included)
- 1 x CR2032 Battery (pre-installed)
Setup & Installation
- Prepare the Horn: Before first use, locate the small plastic insulating piece near the battery compartment. Gently pull and remove this piece to activate the battery connection.
- Attach Anti-slip Pad (Optional): If desired, fix the provided anti-slip rubber pad onto the bottom base of the horn for added grip and paint protection.
- Position the Horn: Place the horn on your bicycle's handlebar in a convenient and accessible location.
- Secure with Strap: Choose the appropriate elastic rubber strap size for your handlebar diameter. Hook one end of the strap onto the horn's base, wrap it around the handlebar, and then secure the other end to the horn's base. Ensure the horn is firmly attached and does not rotate freely.

Image: Visual guide demonstrating the four installation steps for the bike horn.
Video: This video demonstrates the installation process and how to use the ROCKBROS bike horn, including battery replacement.
Operating Instructions
- Activating the Horn: Press the main button on the top of the horn to emit a loud 120dB warning sound. The horn is designed for simple, immediate activation.
- Sound Modes (if applicable): Some models may feature multiple sound modes. Refer to the specific product packaging or additional documentation for details on switching between modes. The primary function is a single, clear warning sound.

Image: The bike horn in action, demonstrating its single warning sound feature.
Video: A short demonstration of the ROCKBROS Electric Super Bike Horn's sound output.
Maintenance
- Battery Replacement: The horn uses a CR2032 battery. To replace, carefully open the battery compartment (a small tool may be required due to the tight waterproof seal). Remove the old battery and insert a new CR2032 battery, ensuring correct polarity. Close the compartment securely to maintain its waterproof integrity.
- Water Resistance: The horn is IPX4 waterproof, meaning it is protected against splashing water from any direction. It is suitable for use in light rain. However, to ensure longevity, avoid submerging the horn in water or exposing it to heavy, continuous rain for extended periods.
- Cleaning: Wipe the horn with a soft, damp cloth to clean. Do not use abrasive cleaners or solvents.

Image: Detailed view of the battery compartment, indicating the CR2032 battery type.

Image: The bike horn shown with water droplets, illustrating its IPX4 waterproof capability.
Troubleshooting
| Problem | Possible Cause | Solution |
|---|---|---|
| Horn does not sound or sounds weak. | Battery is dead or low. Plastic insulating piece not removed. | Replace the CR2032 battery. Ensure the plastic insulating piece has been removed from the battery compartment. |
| Horn is not securely attached. | Strap is loose or incorrect size. | Re-adjust the elastic rubber strap to ensure a tight fit on the handlebar. Use the correct strap size if multiple are provided. |
| Water damage. | Exposure to heavy rain or submersion. | While IPX4 rated, avoid heavy rain or submersion. If wet, dry thoroughly. If damage persists, replacement may be necessary. |
Specifications
| Feature | Detail |
|---|---|
| Brand | ROCKBROS |
| Model Name | 34210002001/US |
| Sound Output | 120dB |
| Waterproof Rating | IPX4 |
| Material | ABS+PC |
| Item Weight | 0.04 Kilograms (34g) |
| Product Dimensions (LxWxH) | 2.9" x 1.7" x 1.7" |
| Mounting Type | Handlebar Mount |
| Compatible Handlebar Size | 22.2mm - 31.8mm |
| Battery Type | CR2032 (replaceable) |
| Sport Type | Cycling |
Warranty & Support
This ROCKBROS Electric Bike Horn comes with a 1-year warranty from the date of purchase. For any questions, issues, or warranty claims, please contact ROCKBROS LLC customer support through the retailer where the product was purchased. Please retain your proof of purchase for warranty validation.





