This aftermarket Vice Block for Springfield XD 40 & XD9 9mm Slides is for securing Springfield pistol slides onto a vice and is specifically designed to fit most XD9 and XD40 pistol slides. The slide vice block makes it easier to work on and service your springfield slide. This is a great way to secure the slide onto the vice jaws to remove and replace the front and rear sights on the pistol slide. Insert the slide vice block onto the frame rail grooves of the slide and mount it onto the jaws of a vice. Gradually tighten the vice jaws onto the slide vice block until the slide is secured, making sure not to overtighten the vice jaw, and you are ready to work on your XD9 and XD40 pistols. This vism vice block for XD9 and XD40 pistol slides is made from hard anodized blue aluminum.