"Manufactured from specially formulated V8 steel alloy for extreme toughness. Features torsion control technology to withstand the stresses of high torque applications. Blue steel impact bits provide a vastly extended working life. Colour coded for convenience. Set contained in a convenient bit storage clip complete with bit holder. Bit sizes: PZ1 x2, PZ2 x 5, PZ3 x1 & PH2 x1.