This addition to the A-3 backpack adds a MOLLE webbing system to the outer perimeter of the backpack, making it easier to attach other small bags for greater ease of use. The backpack itself has three layers, a main pocket, a two-thirds size secondary pocket and a small outermost secondary pocket. Inside the main pocket there is a lined pocket for a 2 litre water bag and liner. The shoulder straps are lined with EVA for extra comfort and have a nylon mesh face with a foam lining. The backpack is breathable. The waist strap is adjustable in length and can be detached as required. The body of the backpack is made of military grade nylon for strength and to ensure that it will not rot when wet. The carry strap is made from automotive seat belt material, which is strong and soft to the touch and comfortable to use.