High quality, industrial grade, professional tools. Made with Eklind Alloy Steel. Heat treated for optimum strength and ductility. Finished with Eklind Black Finish to resist rust. Eklind ball-hex keys will drive a fastener at up to a 30 degree angle Set includes sizes: 1.5mm, 2mm, 2.5mm, 3mm, 4mm, 5mm and 6mm. Color coded blue for Metric. Plastic holder firmly retains each key in a size marked hole. Made in the U.S.A.