1680 DEN Ballistic Nylon outer shell. 420 DEN Nylon inner bladder. Three-piece Form-Harness-System with padded shoulders and back pack for the ultimate in comfort. Quick release buckles on both left and right shoulders for easy removal. Convertible for single cylinder use. Stainless Steel back plate. Anatomically optimized back padding. Adjustable shoulder straps for snug individual fit. 50mm crotch strap with two stainless steel D-rings. Available in 13 kg / 30 lbs and 18 kg / 40 lbs lift capacity.