Smart Sensor Technology: The Bike light for night riding offers a max output of 250 lumens. Under smart mode, light output is locked at 50 lumens for be-seen visibility when the environment is well lit. However, when the user enters a dark area or a tunnel, the brightness automatically increases without any action required.Take Longer Rides Without Worry: These USB-rechargeable bicycle lights can be fully recharged in 3.5 hours. Powered by a 1500mAh capacity battery pack, the lights offer a runtime of 2.5 hours on high, and up to 5 hours on low and flash settings. Each bicycle light undergoes a power test before shipment to ensure quality.Waterproof and Durable: Constructed with high-quality materials and a sturdy rubber strap, our bike light is designed to never detach or fall off. Its waterproof and shockproof features ensure a safe riding experience in any weather conditions.Easy to Install: The compact size and lightweight design make it easy to install on your bike frame with the included mounting bracket. Despite its small size, it boasts an impressive range of up to 100 meters. with a small and lightweight design that makes it easy to carry with you wherever your adventures take you.