The VS insert valves are one-way throttle valves with fixed setting. The passage of the oil is free in one direction and is limited by restrictions on the opposite one. The leakage flow varies according to the pressure drop present at the valve ends. The use of VS insert valves is recommended for working flow rates up to 35 l/min (9.2 gpm), with operating pressures up to 500 bar (7250 PSI). Its dimensions, with external BSPP 3/8” thread, allow the VS resctirctor to be inserted directly inside the users, below the fitting (after checking the useful depth of the thread on use) eliminating the need for additional components such as housing or studs. The simplicity and small dimensions of the valves of the VS series therefore represent optimal characteristics in the design of systems where compactness of dimensions and cost containment are fundamental.