This tool features a durable .004" thick baked on mil-spec finish and is specifically designed to hold and prevent damaging the gas cylinder during gas plug removal. The tool will also conveniently hold the piston to prevent it from rotating during cleaning using a special D-shaped hole built into the wrench. Notes: Springfield Armory rifles manufactured after 2014 have oversized gas cylinders and will require an oversized wrench (Product 560-494)