WACOOL 3L 3Liter 100oz 2L 2Liter 70oz BPA Free EVA Hydration Pack Bladder, Leakproof Water Reservoir Capacity: 3 Liter (100oz), 100% odorless, tasteless, BPA- Free EVA material Might be the most rigid hydration bladder on the market: 0.6mm extra thick liner is pressure-tolerant and wear-proof; double soldering sealing side technique has greatly improved durability. Double opening design. As the most popular design for high end hydration systems in recent years, this allows you to refill in any condition. To avoid potential leaking, the screw cap should be securely closed as tight as possible! Twist the lid clockwise to fasten it tightly until the lid can not move any further under force! Please do not hesitate to mail us first if there is any issue about the product.