The Sioux Chief test titan, mechanical test plug has an innovational approach with a proven performance. Four, non-corrosive components provide a seal to the top of the pipe, while the hollow stem allows for convenient filling/draining though the plug. Polypro wingnut, nylon top plate, soft PVC gasket and nylon base/stem for simplicity and strength. For head tests. Provides a leak free seal at over 8 times the PSI of other mechanical test plugs. Back to front wedge design prevents blowouts at high and low temperatures. Nonslip shoulder for fast, easy installation.