In the event there is over pressurization in the hydraulic system, this by-pass valve will open, allowing the excess water to drain out. It can also be used to adjust the pump dispensing pressure.
The M12 x 1.0 mm female fitting connecting this valve to the pump piston fitting only works on the threads of the Fluid-o-Tech pumps and valve fittings with three exceptions: the Ascaso I.2820 (M x F), I.5213 (M12 x 1/8″) and I.5214 (M12 x M10); no other fittings will work.
1/8″ Female BSP fitting, NBR seal. Fluid-o-tech #B2E.