Mecline VX3 Pressure Regulating Unloader Valves. Hexagonal check valve for a better smoothness. Safety lock at the maximum pressure. Regulation lock for Minimum and Maximum pressure in the knob version. Regulation spring of new concept. New body with inner housing of O-ring in the outlet for a higher resistance. All mechanical parts in stainless steel AISI 303. Ceramic ball. Dynamic O-Ring in FPM (Viton®).