Backpacks 25 liters. Back with cool air system (grid with physical separation), to let the air continuously and can transpire better. Set in the chest and waist for extra support backpack. 600D polyester ripstop fabric (ripstop). -Ax. Compression straps. Cubremochila for embedded at the bottom of the backpack rain. Compatible to incorporate water bag camel bag main pocket. With many intermediate pocket organizers. Side racks. Dimensions: 15x15x50 Cm. Weight: 475 grams.