CNOC Hydriam 28mm Collapsible Bottle 500ml

The CNOC 28mm Hydriam 500 ml is the mid-size model in the collapsible TPU Hydriam line, with a standard 28 mm PCO thread compatible with both Sawyer and Platypus filters. At 26 g for 500 ml capacity, it's among the lightest weight-to-volume ratios for soft flasks on the market, in line with the rest of the series. Collapsed, it packs down to just 7.5 × 4 cm, small enough for the tightest running-vest pocket or a pack's side pocket on a trek. The material is food-grade certified and BPA-free, and the construction is single-wall with no insulation, so don't expect it to hold temperature in either hot or cold conditions. According to the data, the bottle isn't dishwasher-safe, so hand-washing is the recommended route. The screw-cap closure seals tight and the flask is rated leak-proof; thanks to the standard thread, it also works as a direct filter reservoir without needing to decant water into another container.