Greenlee's Standard 9-Piece Folding Hex-Key Set features 9 different sizes for convenience and versatility with a one piece powder-coated handle/case that ensures corrosion resistance. The hex-key set also features laser-etched sizes on the case for easy identification. It is heat-treated and tempered for extra strength and durability. The Standard 9-Piece Folding Hex-Key Set is a great addition to every tool box.