The Delta Series AR-15 Upper Vise Block is optimized for left hand and right hand Mil Spec A2 upper receivers with carry handles, as well as flattop style receivers. Other AR-15 variants may be adapted with special attention to potentially non-conforming surfaces or features. The Delta Series AR-15 Upper Vise Block allows you to safely clamp on to your AR-15 upper receiver in a vise holding it securely without twisting, crushing or marring the finish. This block is the perfect product for torqueing a barrel on, removing a stubborn barrel nut or for simple gun maintenance and cleaning. It is made of a high pressure, solvent resistant polymer material which can withstand almost anythi Mfg: Wheeler Engineering