All bits are made by high quality S2 steel material.Suitable for industrial use Size of 48 pack bits include hex torx square slotted phillips bits-(12-piece metric hex bits:2*1.5mm/2*2mm/2.5mm/3mm/3.5mm/4mm/5mm/6mm/7mm/8mm), (12-piece SAE hex bits:2*5/64, 2*3/32, 7/64, 1/8, 9/64, 5/32, 3/16, 7/32, 1/4, 5/16inch), (12-piece torx bits:T5/T6/T7/T8/T9/T10/T15/T20/T25/T27/T30/T40), (3-piece square bits:S1/S2/S3), (4-piece phillips bits:PH0/PH1/PH2/PH3), (5-piece slotted bits:SL3/SL4/SL5/SL6/SL8) 1/4" extension bit holder with strong magnetic can fit a variety of hexagon tools for any standard screwdrivers and drill.Strong magnetic with good adsorption can fasten bits securely Wide range of household uses for cabinet, door and bed installation/repairing electronic product/tighten or loosen the screws on the bicycle,door, window frame etc.

Can be used with electric screwdrivers, hand screwdrivers, electric drills and any standard drill.Ideal for cars, trucks, machinery and home repair use