Supports the gas cylinder so it won’t be twisted by the wrench when unscrewing the gas cylinder plug. Makes it possible to separate these parts in the field without a vise. Also holds the gas piston stem during cleaning.
Big Book Catalog, Issue:67, Page:486
Law Enforcement / Police Store, Issue:05, Page:048
SPECS: Aluminum. 6" (15.2cm) long x 1½" (3.8cm) wide x 5⁄16" (7.9mm) thick.