Sur-Flo turbine meters with patented paddle stye rotors solve typical turbine meter problems of plugging and impeller breakage. Non-Vent Control Valves for back pressure, pressure reduction, fow control, and compressor suction/bypass applications. Sur-Flo control valves feature a unique axial fow design that offers quick recovery, as well as reduced cavitation, noise, and hunting. Non-venting capability, quickly feld repairable. NEW! Roto-Boss multi-port orifce meter.