CAP TEST COMMON DRN PP 1-1/2INderground use, on cast iron, steel, copper or plastic piping. Designed to fit all drain, waste, and vent pipe materialsin a given nominal size. The convex face allows the cap to withstand greater pressure for testing purposes and minimizes ballooning. To install, simply place over open end of pipe and tighten to 60" pounds torque. Complies with ASTM D5926.