High Brightness & 5 Mode Red brightness( runtime up to 2 hours) Red Strobe( runtime up to 4 hours ) Blue brightness( runtime up to 2 hours) Blue Strobe( runtime up to 4 hours ) Red/Blue Strobe (runtime up to 3 hours) USB Rechargeable Bulit in high quality rechargeable lithium battery, using the most convenient USB charging mode, only takes about 2 hours to fully charge. Easy To Install And Remove Can be mounted vertically or horizontally Quick release rubber strap handle bar/seatpost mount(fits 12-34mm) Specifications: LED Color: Red, Blue Battery capacity: 500mAh Charging time: 2 hours Dimension: 3.4”* 1.6”*4.7” Package Inlcude： 1 x USB Rechargeable Rear Bicycle Light 1 x Rubber Strap 1 x USB Charging Cable. Note:USB Wall Charger( NOT included )