Milwaukee Shockwave impact duty bits are engineered to be very durable. The optimized shock zone geometry is unique For each tip to provide longer life and absorb more torque. The precise fit custom machined tip prevents stripping and reduces wobble, while the custom alloy76 steel proprietary heat treat process maximizes resistance to wear and shock. For use with Torx Security screws. 10 piece set includes: (1) T7 security insert bit, (1) T8 security insert bit, (1) T9 security insert bit, (1) T10 security insert bit, (1) T15 security insert bit, (1) T20 security insert bit, (1) T25 security insert bit, (1) T27 security insert bit, (1) T30 security insert bit and (1) T40 security insert bit.