Hydration Reservoir/Bladder

A hydration reservoir or bladder is a flexible water storage container designed to fit inside a backpack or hydration pack, allowing hikers and backpackers to carry and drink water hands-free through a connected drinking tube and bite valve. These reservoirs typically hold 1-3 liters of water and feature a wide opening for easy filling and cleaning, plus a hose that routes through the pack to the user's shoulder or chest area for convenient access while hiking. They're popular among outdoor enthusiasts because they enable continuous hydration without stopping to retrieve a water bottle, and their flexible design conforms to pack space more efficiently than rigid bottles.