Manufactured from chrome vanadium steel for strength and durability. Ideal for restoring damaged threads in steel, cast, iron and aluminium. Suitable for engine repair and other automotive applications. Set Includes; : 5 x installation tools (various sizes) 5 x break pin tools (various sizes) 5 x twist drills (various sizes) 1 x hex key 5 x taps (various sizes) 110pc wire thread inserts M5 x 0.8 x 6.7mm (x 22) M6 x 1.0 x 8.0mm (x 22) M8 x 1.25 x 10.8mm (x 22) M10 x 1.5 x 13.5mm (x 22) M12 x 1.75 x 16.3mm (x 22) Comes in a metal tin for easy storage and transportation Professional tool for commercial or occasional use.