Anti -impact: The design of these screw knife heads is used to bear high impact because the impact driver can produce a sudden and powerful rotation impact. Anti -impact design helps to prevent drills from broken or damaged in this case. Deep bite design: The deep bite design of the screw knife head makes it more in -depth with the screw head. This can reduce the possibility of head sliding and improve the overall work efficiency by providing stronger connections between the drill and screws. Anti -sliding blade: Screw knife head has anti -ski blades. This design helps to clamp the screws more effectively and reduce the possibility of sliding out of the screw head from the screw head during the operation. The design of mechanical principles: The design of the screw knife head takes into account the mechanical principle. This includes factors such as torque and impact force. The design to that when the impact driver is connected with the screw head, some collision reaction force is absorbed by the torque, which helps prevent head of the drill. Hardness 62hrc: The hardness of the drill head head is equal to or 62HRC (Luo's Class). This high -hardness level indicates that the drill bit material has been optimized for durability and can withstand considerable wear and stress without deformation or damage. note: The words may be different in different batches, but it does not affect the use. Material: Metal colour: Black Package Contents: 12 x screwdriver bit With base 2 x Magnetizer(randomly colored. Cannot be chosen the specific color.) Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.