The Wheeler Rifle Receiver Lapping Tool helps "true" your upper receiver for precise barrel fit and maximum accuracy. Includes flex driver shaft, 220-grit lapping compound, and steel lapping bar. Your choice of AR-10 or AR-15 lapping tool. Compatible with battery-powered or electric drill Steel construction with black oxide finish Includes flex driver shaft, 220-grit lapping compound, and steel lapping bar Your choice of AR-10 or AR-15 lapping tool Order today!