These stainless steel mechanical face seals, also known as pump shaft seals or mechanical shaft seals, are designed for OEM and replacement use on chemical and fertilizer pumps, trash pumps, pressure booster pumps, straight centrifugal pumps, sump pumps and home water systems. The seal components are locked together by a crimped outer shell providing a unitized construction for the diaphragm and drive gasket. This prevents reverse thrusts from dislodging the seal components. This mechanical lock eliminates the need for adhesives thereby eliminating leaks between the seal ring and the diaphragm. All springs and spring retainers are 304 Stainless Steel. All other metal parts are Type 304 Stainless Steel unless otherwise noted.