Designed to minimize flow losses and hydraulic shocks in pumping systems, Models 80E VFD and 100E VFD can be installed in horizontal or vertical piping. Units have unleaded alloy body available with 1, 2, 3, and 4 in. threaded female NPT connections. With guided poppet system, valves automatically adjust noiselessly from high to very low flow rates. Radiuses of valve seat allow self-cleaning, one point swiping action by radius-edged custom molded rubber seal disc.