OE Stanadyne Pressure Regulator Sleeve 27917 with O-Rings and Filter Screen. Does NOT include the 3 internal parts (Spring, Piston and adjusting screw) These vary by pump number, we can help you find these items if needed. Count the # of turns to remove adjusting screw, it is a setting. Please Note: Your fuel injection pump is a very technical devise. Not only does it control your engine it also protects it as well. However, extra care must be used as serious pump and or engine damage can occur. A person repairing their own injection pump is assuming their own risk.