Feature: 1. Fashion design--reflective stripe. 2. Breathable mesh fabric on the back. 3. The buckle design facilitates the fixation of the helmet. 4. Large main pocket. 5. Can accommodate water bags and replenish water at any time. Specification: Material:waterproof nylon Size: 27*14*45cm (L*W*H) Notes 1.Manual measuring,please allow slightly measurement error. 2.Due to the difference between different monitors and lighting effects,the actual color of the item may be slightly different from the color shown on the picture