Reflex Rack is compatible with all three major attachments for rear rack lights making it highly versatile. The reflector will provide rider safety both while on or off with independently functioning reflector serving as reliable backup. Rear rack light with a built-in reflectorCompatible with 50mm, 80mm and 19mm (center mount)220 hours runtimeMeets light standards (StVZO, RKF and Danish)Meets reflector standards (StVZO Z, BS, UN IVA, UN IA and CPSC)Tool free 2 x AA battery exchangeLow battery indicatorIPX4 all weather resistant Note: TL-LD580G REFLEX RACK is a rack only safety light. There are no adapters prepared to mount Reflex Rack to the seat post, seat stay nor any other place than compatible racks.