The Hex Keys in this Irwin 8 piece T Handled Hex Key Set are manufactured from high-strength and durable chrome vanadium steel with an ergonomic design to ease gripping and handling, improving the torque performance. The keys also have a special surface treatment to prevent oxidisation and corrosion. 8 Piece set containing 2.0mm, 2.5mm, 3.0mm, 4.0mm, 5.0mm, 6.0mm, 8.0mm and 10.0mm.