The Spline Drive Breech Lock Bushings 4-Pack offers a quick, easy and efficient solution for die installation in your press. The newly designed, easy-grip splined drive surface ensures fast and accurate die changes with minimal effort. To eliminate confusion, the bushings are anodized and color-coded, allowing you to "color code" your dies for quick, positive identification. These quick-change bushings eliminate the need for traditional lock rings on your dies. Simply tighten the hex clamp screw and the split collar securely locks the die in place. Loosen the screw and the die spins freely for easy adjustments. Once set, these bushings ensure that your dies stay locked in position, making your reloading process smoother and more efficient.