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The collapsible Softflask 500 is particularly convenient for climbers, hikers, and backpackers. It shrinks as you drink until it's the size of a stack of papers that fit in the palm of your hand. That means you can store it in your backpack regardless of how much gear you have in there. Its wide screw cap is easy to fill, and the twist lock ensures that it won't leak. The soft silicone bite valve is easy to drink out of when you're on the move.
The 11.8 fl. oz. Hydrapak SoftFlask 350 Outdoor Collapsible Bottle makes keeping hydrated simple. It's got a large filling port, a handy shut-off valve and a design that stores easily in your pocket.
The Soft Flask Outdoor by Hydrapak adds three new sizes with larger filling ports, shut off valves, and optional hand strap, dust covers, or carrying loops. These SoftFlasks are the same high-performance, collapsible material as the original versions but now with more fluid capacity in a drink delivery system thats easily compressed and stored with modular capability.