ITEM NAME:5X/Set Magnetic Triangle Head Screwdriver Bits S2 Steel 1/4 Hex Shank 50mm MGAU.It made of high-strength S2 alloy steel, very durable. Material: S2 Steel. Magnetic bits, in the installation can easily absorb screws. Hex Shank Size: 6.35mm (1/4"). Bits specification: Δ18; Δ20; Δ23; Δ27; Δ30.