Hydraulic Knock Off ValvePN: 14700540 This End of Stroke Device Cutoff from Hyva Corp works the same way as a pull off cable, except better. Shutting the pump off at the end of the cylinder stroke before over extending. Recommended to use on all dump cylinders, the Knock Off Valve protects against over pressure at the end of the stroke, preventing dead heading and ensuring longer cylinder and pump life. Can also save time, by not having to slow cylinder down and "guess" where