Mod 1 Backpack is a versatile pack with large main compartment, one large & two small additional compartments and one compartment for hydration bladder including outlet for the tube. The total volume is approximately 21 liters, additional pouches (available optionally) can be attached on the MOLLE pals. Both sides are equipped with compression straps. The pack is made from 600 denier polyester which features a good ratio between weight and robustness.