Kingston Model 259 Quick Opening Flow Control Valve features a forged brass body, a brass stem and stainless steel spring. The valve body is is designed with a special stem threading for attaching the valve just below the stem. Ethylene Propylene disc and O-Ring provide a positive seal and are more durable when working with harsher solutions. Lever Option - O, No Lever. The Kingston Model 259 Quick Opening Flow Control Valve is designed for liquid, compressed air or gas applications with a maximum working pressure of 150 psi. The o-ring seal options are available for this valve are Buna-N, Ethylene Propylene and Viton. Disc options are available are the same with the addition of a Teflon Disc option. Lever, spring and cap options also available. See Kingston 250 Series Options Page for more detail. The Kingston Model 250 Series Flow Control Valves were all developed for use in car wash, carpet cleaning and other systems that require a durable control valve using mechanical contact to operate the valve.