HydroBlu Collapsible Canteen

The HydroBlu Collapsible Canteen is a 1.9-liter foldable water container made from BPA-free plastic, designed as a universal reservoir for gravity filtration in the field. Its 28 mm screw cap matches the standard thread used by the HydroBlu Versa Flow and several other filters of the same size, so the canteen serves as the "source" vessel that gravity-feeds water through a filter into a clean bottle or bladder. At 43 g the empty canteen barely registers in a pack, and once the water is used it collapses down to a small footprint. A carabiner loop makes it easy to hang from a pack or tree branch when running a gravity setup, while the single-wall, uninsulated build means it won't hold water temperature — fine for short-term use with either cold or warm water, but not for extended thermal retention. For backpackers who need a simple, light container for raw water ahead of filtration, the HydroBlu Collapsible Canteen is a practical, inexpensive option compatible across several filter systems.