1. Introduction
The ANTUSI Q3 is an intelligent brake-sensing taillight designed for bicycles, enhancing safety and visibility for road bikes and MTBs. It features a durable aluminum alloy body, IPX6 waterproofing, and multiple lighting modes with smart sensing capabilities.
2. Safety & Warnings
Please read all instructions carefully before use to ensure safety and prevent damage to the device.
- Warning: Keep the device and its cord out of reach of children under 3 years old.
- Ensure the taillight is securely installed before riding.
- Do not disassemble or modify the device, as this may void the warranty and pose a safety risk.
3. Package Contents
Verify that all items are present in your package:
- 1 x Q3 Taillight
- 1 x USB Charging Cable
- 1 x Seatpost Bracket
- 1 x Saddle Bracket
- 2 x Bandages
- 4 x Cable Ties

4. Specifications
| Feature | Detail |
|---|---|
| Product Name | Q3 Intelligent Brake Sensing Tail Light |
| Net Weight | Approx. 33g (including seat arch support) |
| Dimensions | Approx. 30 × 34 × 34 mm |
| Shell Material | Aviation aluminum alloy + PC plastic |
| Appearance Features | CNC edge-cutting process, metallic texture, shock-resistant and wear-resistant |
| Waterproof Rating | IPX6 |
| Battery Life (Flashing) | Up to 30 hours |
| Battery Life (Constant Illumination) | Up to 12 hours |
| Charging Time | 1.5 - 2.5 hours |
| Battery Type | Polymer lithium battery |
| Battery Capacity | 300mAh/3.7V |
| Working Temperature | -10 to 60 °C |
| Lighting Modes | Slow flash, breathing light, fast flash, constant illumination |
| Intelligent Sensing | Yes |
| Support Dimmer | 2 - 4 Files |
| Origin | Mainland China |



5. Features
- Smart Auto Brake Sensing: Equipped with intelligent sensors, the ANTUSI Q3 automatically activates upon braking, providing immediate and enhanced visibility to prevent rear-end collisions.
- Durable Construction: Made from aviation aluminum alloy and PC plastic with a CNC edge-cutting process, offering a metallic texture, shock resistance, and wear resistance.
- IPX6 Waterproof: Designed to withstand various weather conditions, ensuring reliable performance in rain and snow.
- Multiple Lighting Modes: Offers Slow Flash, Breathing Light, Fast Flash, and Constant Illumination modes to suit different riding conditions and preferences.
- Long Battery Life: Provides up to 30 hours in flashing mode and 12 hours in constant illumination, with a quick charging time of 1.5-2.5 hours.
- Dual Mounting Options: Includes both seatpost and saddle brackets for versatile and secure installation on most bicycles.
- Low Heat Emission: Operates at a low temperature of 105℃, ensuring safety during rides.

6. Setup (Installation)
The ANTUSI Q3 taillight offers two installation methods: saddle bracket and seatpost bracket.
6.1. Saddle Bracket Installation
- Attach the mounting accessories to the saddle rails.
- Fix the bracket securely with cable ties.
- Cut off any excess cable tie material.
- Install the taillight into the bracket by twisting or sliding it into place.
- Ensure the installation is completed and the light is firmly attached.
6.2. Seatpost Bracket Installation
- Attach the mounting accessories to the seatpost.
- Choose a fixed location on the seatpost for optimal visibility.
- Secure the bracket with the provided bandage.
- Install the taillight into the bracket by twisting or sliding it into place.
- Ensure the installation is completed and the light is firmly attached.



7. Operating Instructions
After installation, turn on the power. The taillight will automatically turn on when the vehicle brakes, and will stay on or flash normally while riding.
7.1. Power On/Off and Mode Switching
The taillight features a mode switch button. Short press the button to cycle through the different lighting modes. The light will automatically adjust based on ambient light conditions (day/night) and brake sensing.
7.2. Lighting Modes
The ANTUSI Q3 offers 4 distinct lighting modes, accessible via a single click:
- 1st Gear: Slow Flash Mode (Smart light sensor mode + Smart brake mode + Smart ON/OFF)
- 2nd Gear: Breathing Light Mode (Smart light sensor mode + Smart brake mode + Smart ON/OFF)
- 3rd Gear: Fast Flashing Mode (Smart brake mode + Smart ON/OFF)
- 4th Gear: Continuous Lighting Mode (Smart brake mode)

7.3. Charging the Taillight
Use the provided USB charging cable to charge the device. The charging indicator will show the charging status:
- Blue light always on: Device is currently charging.
- Light off: Device is fully charged.
- Blue light keeps flashing: Prompts to charge the device.
You can charge the taillight using a 5V adapter, computer USB port, or a mobile USB charger.

7.4. Brake Sensing Function
The intelligent sensor automatically detects when you brake, increasing the brightness of the taillight to alert vehicles behind you. This feature significantly reduces the risk of rear-end collisions.

8. Maintenance & Storage
8.1. Cleaning
Turn off the device before cleaning. Use a soft, lint-free cloth to wipe the taillight. Do not use abrasive cleaners or solvents.
8.2. Storage
Store the device in a dry place at room temperature (15°C - 35°C).
8.3. Long-term Storage
If the device is not used for a long time, charge it to approximately 50% every 3 months to maintain battery health.
9. Troubleshooting
If the taillight is not functioning as expected, please check the following:
- Light not turning on: Ensure the battery is charged. Connect it to a power source using the USB cable.
- Light not responding to brakes: Verify that the taillight is securely mounted and the sensor is not obstructed.
- Intermittent operation: Check for any loose connections or damage. Ensure the device is within the recommended operating temperature range.
- Charging issues: Try a different USB port or charging adapter. Ensure the charging cable is not damaged.
If problems persist, please contact customer support.
10. Disposal & Recycling
This product should not be treated as household waste. According to the WEEE Directive (2012/19/EU), it must be disposed of at an appropriate electronic waste collection point for recycling to prevent potential negative consequences for the environment and human health.
11. Manufacturer & Support Information
Manufacturer: Anfu County Yunkang E-commerce Co., Ltd.
Address: Room 1001, Unit 1, Building 6, Jiangjing No. 1, 921 Gongyuan Road, Pingdu Town, Anfu County, Ji'an City, Jiangxi Province, China
Email: ziuaini520@163.com
Phone: +86 18927421085
EU Authorized Representative: REPLAB SARL
Address: 99 AVENUE ACHILLE PERETTI 92200 NEUILLY-SUR-SEINE France
Email: EUREP@REPLAN.CC
Phone: 33-767189223
For further assistance or inquiries, please refer to the User Manual (PDF).