It is used to regulate the oil in one sense and have the full flow on the opposite one, it is not pressure compensated so the setting depends on the application pressure, the oil viscosity and the oil temperature. The sizes range includes several threads starting from 1/8 BSPP up to 1/2 BSPP. Setting is made by rotating the pin clockwise and vice versa by an Allen key inserted on the upper side of the pin. Once the valve is set, tighten the nut placed closed to the pin. This version does not have the external thread for nut tightening. It does not allow leakages. The external body is made of high resistance steel and externally protected from oxidations by zinc treatment. On request we can supply a zinc/nickel treatment to increase the oxidation resistance when the valve has poor protection or it is located in external environments.