The wrench head is made of high quality steel, which is and has long service life. Hexagon socket is suitable for machinery workshops, automobiles, construction machinery, industry and other equipment. Equipped with plastic storage box, portable storage. This product has higher hardness after high temperature quenching, and it is not easy to break and damage. Name: socket head of electric wrench Model: 8,9,10,11,12,13,14,15,16,17(mm) Colour:black Material:steel Package Contents: 10 x Socket head of electric wrench Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.