about this project 5-in-1 Bicycle Tail Light: Practical and multifunctional bicycle accessories. It works as a warning light/brake light/turn signal light/electric bell/anti-theft siren. Comes with a remote control, easy to install and use. This bicycle alarm tail light can ensure the safety during riding and let you enjoy the fun of riding. ULTRA BRIGHT BIKE LIGHT: The Mammoth Bike Tail Light has 31 built-in LEDs and a brightness of up to 160 lumens. It's bright enough to be seen from 150 feet away in fog/rain or even at night. IP54 waterproof housing can effectively protect it from rain and other bad weather. Brake sensor light: Automatically turn on the high brightness mode when braking, the high lumen red LED light will make you more eye-catching and warn the drivers behind you to improve your safety. Anti-Theft Alarm & Bike Horn: Press the arm/disarm button of the remote to activate the alarm, once vibration or movement is detected, the alarm will be triggered, 110dB loud alarm and bright red light will be a good deterrent. Press the central bell button, the 110db chime will alert you to cars, pedestrians or animals around you. 3 horn sounds to choose from. USB Rechargeable Bike Tail Light: No more hassle of changing batteries. Simply connect the tail light to a power bank, PC or AC adapter to charge. Please use the original USB cable to fully charge the device before first use. Specification: Waterproof grade: IP54 Working frequency: 433MHz Working temperature: -40+60 Working humidity: <80% Tail light battery: 3.7V 2000mAh lithium battery (included) Rear Light Charging Port: Standard USB-C, 5V Tail Light Dimensions: 4.9 x 1.3 x 3.8 inches (125 x 33 x 97 mm) Tail Light Holder Diameter Range: 0.98 to 1.38 inches (2.4 to 3.5 cm) Alarm volume: 110 dB Remote control battery: CR2032 battery Remote Dimensions: 1.8 x 1.6 x 0.7 inches (45 x 41 x 17mm) Remote control distance: up to 98 feet (about 30 meters) Remote control bracket diameter range: 0.78 to 0.94 inches (1.9 to 2.3 cm) Please note: 1) Before first use, please charge the device to activate it. Charging is complete when the 4 LEDs on the right (3 small + 1 large) are solid on. 2) Plug not included. Please connect the taillight to a PC or mobile power supply, or use a USB cable + mobile phone plug to charge.