1.Package Contents: you will receive 4 pieces of water backpacks with bladders, adequate in quantity, allowing you to equip your family or friends with these versatile hydration backpacks for group adventures 2. and Practical: our hydration pack is designed with reliable material, with a size of about 18 x 8.5 inches, portable to carry, and provides enough storage and portability, and it can keep stable on your back, letting you enjoy outdoor activities 3.3 Liter Hydration Bladder: our water pack for hiking is equipped with a 3 liter hydration bladder to hold enough fluid when you exercise, the ample capacity allows for prolonged outdoor activities without the need for frequent refills, ideal for hiking, camping, cycling, and other adventures 4.Reliable Material: crafted from quality oxford fabric, our hydration backpack pack is built to withstand rugged outdoor conditions, not easy to break or scratch, the sturdy material ensures long lasting use, making it a reliable companion for outdoor enthusiast