CNOC Hydriam Collapsible Bottle 500ml 42mm

The CNOC Hydriam 500ml is a collapsible TPU soft flask weighing 31 g, with the same tapered base as the larger Hydriam sizes so it fits into running-vest and backpack shoulder-strap pockets rather than needing a main compartment slot. The 42 mm neck is compatible with Katadyn filters, letting it work as a filter reservoir as well as a personal drinking bottle. Food-grade, BPA/BPS-free TPU packs flat once emptied, and at 500 ml it suits day hikes, trail running, or as a secondary bottle on longer trips rather than being the sole water-carrying capacity for a multi-day trek.