Red Head Multi-Set Depth Charge 3/8 Inch Diameter Drill Bit is used for RX Drop-In anchors. The shoulder prevents over drilling, making it less likely to hit reinforcing steel or post-tension cable in concrete. This drill bit allows for no lost time or energy drilling farther than necessary, and since the anchor is set at a specified depth, it does not drop too far into hole. The drilling depth for this bit is 3/4 inch.