This is a new replacement for the GM 22536997 heater hose insulator/washer attaching screw. Made to the same specifications, it's painted black and designed for under-hood use. Your GM vehicle used one of these screws to attach the heater hose assembly to the firewall. Note that this part is obsolete from GM and is no longer included with the 10256543 and 10256544 heater hose assemblies. We also have the 10253680 heater hose insulator/washer.
This item must be shipped in a small box.