Half the price of the other brand that other brand named mw. (which i also own and is great for my - Presma .308 Barrel Vise Block Rod w/ Torque Block for .936

When you get this, the notch on the top will be flush with the rod. You'll need to loosen the set screw on the side to get it to come out. Then screw in the set screw and allow the tab to sit on top. When you slide it into the receiver, it will also secure itself to the receiver from rotating against the rod. Great for when your tightening a barrel nut, so all the pressure from the receiver isn't against the indexing pin on your barrel.