CNOC Hydriam Collapsible Bottle 350ml 28mm

The CNOC Hydriam 350ml is the smallest bottle in the Hydriam line, a collapsible TPU soft flask weighing 21 g. Its 28 mm neck threads straight onto Sawyer and Platypus filters; the larger Hydriam volumes are also offered with a wider 42 mm mouth for Katadyn-style fittings. At 350 ml and 21 g it packs down to a genuinely tiny size once empty, making it more of a backup or minimalist filtering vessel than a primary water-carrying bottle - useful clipped to a vest or stashed in a hip-belt pocket for topping up at a stream rather than as your main hydration capacity on a full day out.