Camel Bak's most technical running pack, the Ultra 10 was designed to endure one of the toughest trail races on earth: the Ultra Trail du Mont Blanc. Camel Bak engineered this pack to carry every item on the UTMB gear list: a two-litre reservoir, room for food & extra layers, a sweat-proof pocket for your smartphone & two chest pockets for additional water bottles. If it works on Mont Blanc, it can handle just about anything. Refilling on the run? Camel Bak have added color-coded straps so you'll instantly know how to access your water supply, & an external-fill design that lets you refill without unpacking the bag. On hot days, fill the reservoir with ice water – the mesh back panel lets it sit against your back to cool your core. Camel Bak have also included overflow storage, trekking pole attachments & plenty of lash points, just in case you want to bring something they didn't think of. The custom-fit harness & dual sternum straps adjust for a close, comfortable fit, & the cargo compression lets you cinch everything down to minimize bulk.