The slide vice block makes it easier to work on and service the slide. Insert the slide vice block onto the frame rail grooves of the slide and mount onto the jaws of a vice. Gradually tighten the vice jaws onto the slide vice block, until the slide is secured. Do not overtighten vice jaws. Features : Anodized Blue aluminum Designed to fit most of the Standard, Compact, Subcompact framed models: 9mm, .40, .45, 10mm, .357 SIG, .45 GAP This slide vice block will not fit compact/subcompact slimline models: 42, 43, 43X, 48 GLOCK is a registered trademark of GLOCK Inc. 3CR Tactical is not affiliated with, endorsed by, or sponsored by GLOCK Inc. Any reference to GLOCK products is for identification and compatibility purposes only.