The topeak whitelite mega 10w power pack is a spare battery for your whitelite mega light providing up to 20 hours of light you can be guaranteed full visibility for your ride with a charging time of 5 to 6 hours you can be ready for everyday riding within a matter of seconds topeak whitelite mega 10w power pack features compatible whitelite hp mega 10w battery 37v 10400 mah lithrsquoion burn time 10w ndash 3 hours 5w ndash 6 hours blinking ndash 20 hours charge time 5