This is an aluminum valve supplied with a stainless steel retainer. This valve will be found in the automatic fuel shut-off assemblies on models 50/520/530/60/620/630 tractors. This valve may also be used in the cranking engine shut-off assemblies as well. Sometimes when re-building a used assembly this part may be missing or damaged. We offer this part to complement our rebuild kit for these shut-off assemblies.