Designed for use with the WhiteLite Mega 10W lamp the Topeak Powerpack For Mega extends you ride. This compact, lightweight and powerful Lithium Ion PowerPack is stem mounted via a strap to keep the cable routing short and provides up to 6.5 hours of run time. Charge time 5-6 hours. Use as a backup Topeak Powerpack For Mega or as a perfect way to extend your night rides until dawn. Features: 3.7V 10400mAh Lithium lon battery pack Burn times: 3.5 hr 10W / 6.5 hr 5W / 24 hr Blinking 5-6 hr charging time Stem Mount with hook & loop fastener 0.5 hr 2.6W reserve power Weight: 255 g