COLOR MAY VARY.308 Barrel Vise Block Rod for .936" - AR-10 LR-308, Black. SKU AV3Really cool tool for working on your AR build. This multi-use tool helps with ease of installation of barrel nuts without scratching the exterior. Also a great way to securely hold your AR's upper receiver assembly for maintenance and upgrades. Comes with carrying case/holder.These tools are made to grip in a bench vise so that the rod is either vertical or horizontal. You then slide the upper receiver onto the reaction bar. The splines on the front of the rod enter the into barrel extension for a secure hold and fit. Ready for tuning, it's that simple.12" in Length. Color anodized. Tips are 7075 Aluminum and base is 6061. Will handle 70+ ft lbs of torque.