Premium MaterialThe inner layer of this Hydration Bladder is made of PE material, and the outer layer is made of EVA material, which is wear-resistant and anti-corrosion, BPA-free,Odorless and non-toxic, it is safe for drinking.Leakproof Design: The water reservoir bladder passed pneumatic pressure test, it is completely pressure-tolerant. Double sealing side technique has greatly improved durability. Auto shut off while the tube is removed, supply the 2 liter water reservoir will stay filled non-leaking.Big Opening, Easy Filling And Clean: The wide opening is large enough for your hand to clean the hydration bladder, easy to fill water and add ice cubes.The big opening allows you reach into corner inside to give your water reservoir bladder a thorough cleaning.2L Large Capacity: This water bladder bag is 2 Liter. It is the best choice for outdoor, enough for a day drinking of hiking, cycling, climbing, running or biking. 34 x 17 CM in size, the hose length is 100 cm, long enough to drink it straight from the backpack.Perfect For Hydration Backpack: Compatible with most hydration packs, simply fill with fresh water and insert into a backpack. To hydrate, gently bite the valve and sip as you would from a straw. Ideal for all Kinds of Outdoor Activities, Like Hiking, Cycling, Marathon, Camping, Climming, Running, Skiing, Jogging.