POWERFULL SAFETY AND SECURITY FEATURES: High lumen COB led, auto on off flashing light ,super loud sensitive siren, remote panic alarm make it both improve your visibility to ensure your riding safety and scare away a thief to protect your bicycle3-LEVEL ADJUATABLE BRIGHTNESS WITH 4 LIGHT MODES : The taillight has 3 levels of brightness adjusted by the remote and 4 lighting modes, which give the ride a ability to tailor the light intensity and blinking options to your needs and light conditions3 LEVELS ADJUSTABLE VOLUME AND SENSITIVITY: With115dB horn, motion senor and vibration detector, a slight touch can active a high pitched alarm and scare off thieves. Volume and sensitivity can be adjusted to meet your needs and individual situationUSB-C RECHARGEABLE LONG BATTERY LIFE: The bicycle rear light is powered by safe and durable 800mAh polymer battery, which make the battery life up to 40 hours. Type-C port design make bike back light easy to fully charge in 3 hours by USB-C cableEASY TO USE: With well designed mount bracket, it's easy to twist the light in & off the base slot for charging. The bracket installs on saddle rail by zip ties or seatpost by silicone strap. IPX5 Waterproof add a protection to use in bad weather