Yeholding Cycling Backpack,Riding Backpack, Riding Bag Bike Bicycle Cycling Bag Hiking Bag 15L Outdoor Running Backpack [Waterproof] [Light weight]+Hydration Bladder 2L (Blue) Reduce the burden system design, much more comfortable. Adjustable shoulder strap and waist strap, thickening and soften back design. to fit your need. Safe and convenient to use, small size. The waterproof nylon fabric,provent the items inside from being wet. Special hole designed for water bag. Net for holding the helmet. Airflow system design, keep your back cool and dry. Integrated breathable mesh pad in the back,breathable and not muggy. Double-layer design, special inner layer for holding water bladder. Including a water tube retainer clip for holding drinking tube. Backpack Capacity:15L, Size: 42cm x23cm x17cm(16.5" x 9" x 6.7"), Weight:465g. Backpack including 2L(70 oz) wide opening water bladder. Hydration Bladder Capacity:2L, size:41 x 7cm /16.1'' x 2.8'', Tube Size: 104 x 1cm / 40.9'' x 0.4''. Weight:130g.