Pump Repair Kit, Check Ball Material Buna-N, Compatible with Grainger Part Number 15U521, Compatible with Manufacturer Model Number S15B1ABWANS000, Diaphragm Material Buna-N, Number of Check Balls 4, Number of Diaphragms 2, Number of O-Rings 0, Number of Seals 0, Valve Type Ball, Product Type Fluid End Repair Kit, Media Intake Pressure (Maximum) 125 psi, Compatible with Pump Type Air Operated Double Diaphragm Pump, Compatible with Brand Sandpiper, Includes Check Balls, Diaphragms, Gaskets, Seals