[Sizes]: Length of 10cm you can probably go anywhere. The sizes are: T6 T7 T8 T9 T10 T15 T20 T25 T27 T30x2 T40 to meet your different needs. [Materials]: Bits are made of S2 steel, heat treated, and with high hardness, the hardness can reach HRC60, the bit surface is sandblasted. S2 alloy steel; Head Type: Torx 12 Pcs 100mm Torx Long Bits Screwdriver Set with 1 Pcs Handle. [Magnetic bits with handle]: Thanks to magnetization, the screws also stick to the bit and especially in deeper holes you don't have to turn/shake the object to get the screw out. [Extra Long Magnetic Bits]: The bit has been magnetized and the length increased to 100mm, which can make your work easier. [Type of shaft]: 6.35 mm, 1/4 inch hex. Material:S2 steel colour:Silver Gray Package Contents: 12 x 100mm Torx Screwdriver Bits 1 x handle Only the above package content, other products are not included. Note: Light shooting 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.