Designed for road biking, running and hiking, this hydration pack is compact and small in size, keeping your back light and stable. It will not move or bounce. Suitable for cycling, hiking, running, skiing, biking, climbing, hunting, racing and training. This water bag backpack is made of waterproof nylon for superior abrasion resistance. Snap zipper fittings are durable and impact-resistant; webbing is strong and fade-resistant. Our hiking water backpack comes with 2L large capacity TPU water bag, 100% BPA free and odor free. And the large capacity of 2L ensures sufficient water supply for a full day of exhausting hiking and trekking. Extra helmet clip closure and rubber band cords make full use of every space in the backpack, designed as a multi-functional backpack.