The HydraPak Stow 350ml transforms the way you think about backcountry hydration by solving the age-old problem of bulky bottles eating up precious pack space. This ingenious collapsible water bottle weighs just 35g and rolls up to practically nothing when empty, letting you stash it in jacket pockets, cramped day packs, or tight gear spaces where rigid bottles simply won't fit. The ultra-durable TPU construction delivers the flexibility you need for roll-up storage while the spill-proof flip cap keeps your gear bone-dry during those bouncy ski descents or stream crossings. Whether you're threading through tight hiking trails, chasing powder on the slopes, or spending long days on the water, this lightweight hydration solution gives you 350ml of reliable water storage without the bulk penalty, plus it doubles as a base for water filtration systems when you need to source water from backcountry streams.