Hydration Bladder, 1.5-2-3L Water Bladder for Hiking Backpack, BPA-Free Leak Proof Water Reservoir Storage Bag, Water Pouch Hydration Pack for Camping Cycling RunningLarge opening for easy cleaning: CHERAINTI 3l hydration bladder has one of large opening, and the big opening makes for easy pouring of water; it is also fairly wide for a hand or bottle brush easily access to the interior water bladder 3l; the screw on cap goes on and off easily; for cold water, simply add ice cubes directly from a scoop or refrigerator ice dispenser; the smooth inner of water reservoir promotes health and is easy to clean Premium