Hydration meets protection camelbak built this pack for enduro courses where riders descend 4000 feet in under 20 minutesand where crashes are inevitable the kudus back protector insert the impact protector absorbs over 94 of impact in a crash and while most back protectors are one hit wonders this one can withstand multiple impacts the impact protector is made of flexible lightweight foam that moves with your body so youll get the protection you need without feeling like a tank