Dual opening design - slider sealed wide opening and standard soda bottle-style screw neck Attaches to filters with a 42 mm thread, such as the Katadyn BeFree Easy to fill and simple to clean and dry due to the wide opening Durable- despite the soft material, the VectoX has a breaking point of 450 lbs Can handle boiling water The VectoX is our true and tested Vecto, but eXtra: more durable, thicker and tougher, for adventurers who demand more from their gear. The VectoX is light, extra durable and easy to handle. It is easy to fill with just a couple of scoops, carry to a dry camp or filter on the spot with a 42mm compatible filter, like the Katadyn BeFree. Leave more time to really enjoy your hike or just time at camp with a quick and simple filtering system.