Size - 42pcs bits(slotted: 3mm/4mm/5mm/6mm/7mm; torx: T10/T15/T20/T25/T27/T30/T35/T40; phillips: PH0/PH1/PH2/PH3, pozi: PZ0/PZ1/PZ2/PZ3; hex: H6/H5/H4/H3.5/H3/H2.5/H2; square: S0/S1/S2/S3), 1pcs 1/4' extension bit holder, 9pcs 5-13mm metric sockets,1pcs magnet ring and 1 pcs 6.35mm/1/4' small ratcheting wrench(100mm/4' length), which are small enough to operate in tight places/narrow spaces/narrow areas. Bit Length: 25mm/1' Material - Those screwdriver bits are made of S2 alloy steel material with a sandblasting finish, high hardness and durability, suitable for industrial use. Features - The drill bit set can be matched with an interface 1/4' torque wrench, ratchet wrench, slide bar, power wrench, and drive square head. The magnetic screw holder ring can magnetize screwdrivers, bits, hex key wrenches, etc., easily and quickly grab the screws and fix them, reducing wear and improving work efficiency.