The Sea to Summit Watercell ST is a lightweight, collapsible water storage bag for backpacking, camping, bikepacking, paddle sports, expeditions, and adventure travel. Its 3D molded shape features an internal baffle for easier filling, packing, draining, and drying. Made from abrasion-resistant, semi-translucent, food-grade TPU, with RF welded seams. The screw-top wide-mouth opening is compatible with industry standard water filtration systems and replacement lids. A low-profile welded fill-handle provides one-handed manageability, while strong, streamlined grab-handles double as lash points. The Sea to Summit Watercell ST is available in three sizes: 4-liter water reservoir measures 11 x 8.5 x 4 inches and weighs 4.4 ounces; 6-liter water reservoir measures 13.75 x 9 x 4.25 inches and weighs 5.3 ounces; 10-liter water reservoir measures 16.5 x 11.25 x 5 inches and weighs 6.7 ounces. BPA, PVC and taste-free. Sea to Summit products are guaranteed against defects in materials or workmanship for the lifetime of the product.