A mechanical seal needs metal parts to hold the other components together in the desired relationship. For example, a retainer in a mechanical seal might be used to package a seal face or ring, secondary sealing element and springs into a single unit. Another example of hardware is the mechanical seal drive mechanism to prevent axial and rotational slippage of the pump mechanical seal on the shaft. Stainless steel 304, 316L, duplex 2205, SS329 and etc.are available
