Tiny but tenacious the Stix Elite tail light packs a 62-lumen punch that can be seen from a multiple of directions. Its wide-angle light & six modes—ranging from steady to flash— make you highly visible to drivers which will increase your safety & peace of mind while riding. The tail light runs for up to 60 hours depending on mode choice & is charged easily & conveniently via USB (Universal Serial Bus).> 12 to 62 Lumens output.> 2.4 hours to 77 hours runtime.> Charge in the USB (Universal Serial Bus) port of any laptop or phone charger in two hours (no extra cables needed).> Flexible mounting system works with seatposts from 22.2mm up to 35mm in diameter plus its compatible with most seatstays (Aero strap mount available separately).> Six operating modes: Steady High 46 Lumens Steady Low 18 Lumens Power Surge 37 Lumens Power Flash 68 Lumens Disco Flash 40 Lumens Eco Flash 12 Lumens> Red/ Green battery charge level indicator.> Additional mounting options available separately.