Yalumi Bike Headlight and Taillight Combinations ADVANCED OPTICAL TECHNOLOGIES- The front bike light produces a bright uniform beam image of 120 lumens and 24 lux at 10 meters in maximum mode The optical design technology creates a light beam divergence range more than 220. EASY TO USE AND INSTALL- The headlight with adaptable design is easy to be mounted onto any size of handlebar. The bike rear light is easily affixed with the flexible long lasting silicone strap. Simple push-button system for quick lighting mode selection (3 modes: economic, high-brightness, strobe). QUALITY HIGH POWER LED- Quality reliable Cree high power white LED with a tailored optical lens creates a uniform shaped beam for long distance illumination HIGHIEST QUALITY- The headlamps are designed for outdoor activity. They are IPX4 rating for water resistance and CE, RoHS compliance.