a27 Equipped with an intelligent light sensor: Equipped with an intelligent light sensor, the brightness of the bicycle light can be automatically adjusted according to the environment by upgrading the light sensor. USB rechargeable and 2200mAh capacity battery: The bicycle light is USB rechargeable and is equipped with three battery indicator lights above the switch. You can know the remaining battery level. Note: When charging, please use a suitable charging device. Easy installation and waterproof IPX65: With a bicycle seat clamp, it can be easily removed from the handlebar holder, and can also be used as a light when removed. It can easily cope with bad weather such as heavy rain. 4-stage lighting mode: There are four lighting modes: light sensor mode -> strong light -> weak light -> strobe (10Hz). *As this is an imported product, there may be small scratches or slight dirt during the manufacturing process. Please understand.