NcSTAR Vice Block Tool, For Standard, Compact, Subcompact Glock Slides, Will Not Fit Slimline Models (42,43,43X,48), Aluminum Construction, Anodized Finish, Blue VTVBGLK 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.