Wilson Combat 414B: BulletProof Slide Stops are fully machined from solid stainless steel bar stock with extra metal left in critical areas for added durability. Still, the real key to a Bullet Proof Slide Stop is the material. BulletProof Slide Stops have a built-in detent, serrated top, and maximum tolerance shaft. This is a drop-in part requiring no fitting in properly manufactured 1911 Autos. It fits All Codes in .45 ACP Pkg.