Constructed from welded thermoplastic polyurethane; the ultralight material is flexible, durable, and abrasion resistant. A wide opening enables easy filling, while the leakproof screwcap is tethered so it can't get lost. With two lash points, you can attach it to your pack; once empty it collapses down to the size of a fist. An innovative alternative to traditional water carriers, use when backpacking, with groups, at festivals - you name it!