XS Scuba's Pro Valves are designed and manufactured for long life and heavy use. The Pro Valve with 1/2" National Pipe Threads (NPT) is no exception. Valve is made of marine grade brass with triple bright chrome plating for long life protection in salt water. Precision machined from high tension brass and chrome plated the valve stems will give years of service and corrosion free operation. Easy grip soft rubber safety hand wheel with stainless steel insert ensures long life and large ribs make turning handle easy even when wearing gloves. This unique safety hand wheel allows the diver to visually see if the valve is completely turned on and off with a set of colored rings that appear on the valve side of the hand wheel. If you see Red" the valve is off. If you see Green" the valve is completely open and ready for diving. This hand wheel takes the guess work out of knowing your valve is fully open and ready for diving. Valve bonnets are O-ring. You won't need to crank" on the valve when you open and close it with the 1.5-hand wheel rotation from full-on to fully-off. The valves seat assembly is Teflon coated for years of smooth operation and a one-piece safety plug protected within the valve body guards against damage during transport. The Pro Valve will accommodate both yoke and DIN cylinders with its Removable 230 bar (3,336 psi) DIN insert which can be removed using a 1/4" hex key wrench. Primarily used for old 71.2 cu. ft. (2016 liter) steel