The ZX/50D has proven itself from the Antarctic to the tropics, in deep technical dives as well as in recreational use.First Stage Specs: Conical Precision HP valve Nitrox compatible to 40% Dry Environmental Seal with Hydro Transmitter Swivel Turret Hose Mount Balanced Diaphragm convenient and ergonomic swivel hose design Yoke or DIN inlet available 4 Low Pressure Ports (3/8-24 UNF) 2 High Pressure Ports (7/16"-20 UNF) Weight 2.1 lb. (.95 kg.) Intermediate Pressure: 135-150 psi (9-10 bar) Second Stage Specs: Downstream valve Balanced Diaphragm Dive/Pre Dive Venturi Control Diver Adjustable Breathing Sensitivity Anti-Freeze heat transfer device Weight: .54 lb. (.26 kg) ( w/o hose) Hose Length: 30 in. (.76 m)