The Hydriam is a soft, collapsible, reusable drinking flask. Perfect for storing water in running vests or for a simple way to carry a flask of whiskey up the mountain, the Hydriam is a versatile and lightweight way to carry whatever liquid you need it to. It features a tapered design that allows them to easily slide into the pocket of a running vest. The back includes markings for measuring out liquids while cooking or mixing your favorite camp cocktail. This flask is available with 28mm or 42mm thread options. The 28mm thread is compatible with filters like the Sawyer or the Platypus QuickDraw, allowing for filtering on the go during long runs or fastpacking trips. The 42mm thread is compatible with the Katadyn BeFree filter. Features Rolls up small when empty Cnoc&';s lightest water carrying container Tapered design to easily fit in running vest pockets 350ml, 500ml, and 750ml volume size options Tethered cap Attaches to filters with a 28 mm or 42mm thread Robust and durable, utilizing the same material as the Vecto FDA approved and BPA, BPS, and BPF free Please note: TPU is a porous material and so is not completely smell free after production, please clean and air prior to use. Specifications Capacity: 750 ml / 25 oz Packed size: 4x1.5x1.5 in / 10x4x4 cm Trail size: 11x4 in / 28x10 cm Weight: 28 g / 1 oz Material: Bladder - TPU | Cap - PP Operational temperatures: 20AdegF (-6AdegC) to 120AdegF (49AdegC) Place of production: China