The nut is made of chrome molybdenum steel, with high hardness, ensuring a service life and durability3/8 inch opening reverse screw damaged/rusted nut screw extraction sleeve provides maximum grip and easy removal of damaged or rusted nuts, screws and bolts.The surface is electroplated and blackened, which is corrosion resistant and rust resistant, and has high hardness after secondary heat treatment.color: Blackmaterial: metalPackage Contents:13 x Nut Remover1 x Hexagon screw socketOnly the above package content, other are not included.Note: Light reflection and different displays may cause the color of the item in the a little different from the real thing. The measurement allowed error is +/- 1-3cm.