Incredible high power rear with a multitude of settings to suit your riding environment. Powerful yet sensitive…be seen, be safe, wherever you ride. • High power rechargeable rear light with up to 50 lumen• Interchangeable cartridge Li-ion battery• Superlight – 120g• USB recharge to head unit• Cartridge rechargeable docking station (sold separately)• Great side visibility• Seat rail mount (included)• Helmet mount (optional)• Seat post mount (optional)• 4 modes: Constant / Flash / Hyper Constant / Pulse• Runtimes: C:8hrs / F: 20hrs