About this item 1.【High Quality S2 Steel 】Made of high-strength S2 alloy steel, for best durability and low wear. 2.【Sizes Included】 Triangle head screwdriver bits sizes: 18 (1.8mm), 20 (2.0mm), 23 (2.3mm), 27 (2.7mm). The mini handle screwdriver size: 12mm length, suitable for the 1/4 inch (6.5mm) hex shank screwdriver bit. 3.【Magnetic Triangle Head】Magnetic screwdriver bits, anti-rust, anti-skid, can easily absorb screws, no damage to the screw and the screwdriver head. 4.【Widely Used】Our triangle head screwdriver bits set is widely used power tools, electric screwdriver assembly, electronics industry, household appliances, precision instruments industry, furniture industry screw equipment. 5.【 Application】Suitable for installation in handle screwdrivers, pneumatic screwdrivers, electric screwdriver, rechargeable drill, using the wind batch.