Carry your whole day on your back while keeping your devices charged this sleek, yet bomber, top-loading pack that's designed to haul 23.5-liter loads on foot or by bike. This minimal design stands up on its own for easy access to gear and is crafted of the same indestructible water-resistant material that's used to transport gear on yaks during high-alpine expeditions. The 17" laptop pocket connects to the lightweight, large capacity Joey™ T55 power supply through an integrated cable system. The rugged water- and crush-resistant lithium polymer battery provides three-and-a-half full battery charges or several days of partial charges to your cell phone, MP3 player, tablet, or other USB devices. For the ultimate in versatility, the Joey™ power supply can also be removed and used as an emergency power supply in other packs.