This 1/2" thick (0.470" actual) carrier bearing or center support shim is machined from 304 stainless steel and is designed to work with carrier bearing Spicer part # 211359X.

Some Super Duty trucks come with a 1/2" thick shim welded to the original OEM carrier bearing.  If replacing a worn out carrier bearing with a Spicer unit, it may not come with the required shim - this shim is a great solution.

*Note: 304 stainless steel has good corrosion resistance, although light surface rust is still possible.