MASTER GRADE A2AR15 WRENCHES TORQUE WRENCH MasterFit single purpose crowfoot wrenches are made specifically for the job. Specialized for precise fitment and manipulation of A2 barrel nuts buttstocks muzzle devices and castle nuts. Titanium coated stainless steel construction provide tight tolerances for solid nut gripping strength and enhanced noslip fitment. Paired with the heavyduty MasterFit Torque Wrench it takes Gun DIY building to a new level of Master Grade quality and precision.