Made of chrome vanadium steel with long life and durability. Strong inner hex sleeve without magnet. This screwdriver bit set comes with a fits most corded or cordless drills to drive hex head screws. 9 hex sockets: 5mm, 6mm, 7mm, 8mm, 9mm, 10mm, 11mm, 12mm, 13mm. Many applications. Suitable for DIY, woodworking, auto parts, professional machine repair, etc.