Foldable waterproof backpack $ 28.61 Bag size: medium Capacity: below 20L Internal structure of the bag: zipper pocket, mobile phone bag, ID bag, sandwich zipper bag, computer pocket Opening method: zipper Applicable gender: neutral / male and female Material: Polyester Function: breathable, waterproof, wear-resistant, anti-theft, anti-seismic, lighten Processing method: printing Hardness: Medium pattern: plain style: Casual Lining texture: Polyester Strap root number: double root Popular elements: folding Lifting parts: soft handle Type of outer bag: inner patch bag Bag shapes: square vertical section Carrying system: air cushion strap