(1)Made of chrome vanadium steel with long service life.(2)The set includes: 9 Power Nut Driver bits (metric): 5mm, 6mm, 7mm, 8mm, 9mm, 10mm, 11mm, 12mm, 13mm.(3)The product is easy to install and disassemble and will not come off easily during use. Anti-rust, anti-slip, high occlusion, waterproof and flexible.(4)It is widely used in DIY supplies, auto parts, woodworking, professional machinery, in hexagonal tools such as pneumatic lathe, electric lathe, pneumatic drill, electric drill, pistol drill, manual screwdriver.