The ST line of wings are for single tank diving. The design features a 360 degree tapered profile, to increase lift towards the hips, promoting better horizontal trim in dive position while still allowing perfect surface floatation. The ST22 is designed for warm water dives in aluminum cylinders, where low lift and maximum streamlining is preferred. Alternatively the ST35 is an excellent choice for a go anywhere wing with the added lift for those local cold-water dives and heavier steel cylinders but still streamlined enough for travel destinations. Tank slots and tank cradle are included on both models, which allows you to connect your wing and backplate without the need for a single tank adapter plate. This reduces weight and unnecessary accessories while traveling. The bladder is a two-piece design, with a rugged 1680 Cordura nylon outer shell to prevent abrasion and punctures, and a 420-denier nylon inner bladder to maintain the buoyancy. The lower OPV is easy to reach for venting gas while horizontal or heads down, and the inflator design is a K style with a rugged crushproof rubber hose for easy positioning and oral inflation should you need to. ST35 - 35lbs lift / 16 kg Welded flange and one piece retainer for servicing without the need for tools HD Laminated 1680D Cordura outer shell 420 nylon internal bladder Elbow offset to avoid tank valve/regulator interference and streamlined hose routing Lower left pull relief valve Cam band slots & tank cradle built in 5 YEAR WARRANTY