Fortis Manufacturing, Inc. Billet Magazine Catch and Release, Nitride Finish, Black, Fits AR-15 AR15-BMCR-BLK The Fortis Billet Mag Catch & Button is a superior alternative to the ones found in a mil-spec lower parts kit. Easily installs in seconds and instantly upgrades your rifle. This upgrade is CNC machined from a solid piece of 6061-T6 aircraft grade aluminum or 303 Stainless Steel. There is an added texture and engraved logo for just the right touch of function and styling. Magazine rod is 303 Stainless Steel for further added durability.