Designed with a ball profile on the long arm, this feature provides 360 degrees of rotation at up to a 30 degree angle. 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. Red plastic holder firmly retains each key in a size marked hole This long series key set includes sizes: .050, 1/16", 5/64", 3/32", 7/64", 1/8", 9/64", 5/32", 3/16", 7/32", 1/4" , 5/16", 3/8". Made in the U.S.A.