Machine Key Length 3 in Length Tolerance +0.000/-0.100 in Material Steel Material Grade/Class Ungraded Finish Plain End Profile Tapered Gib Width Tolerance +0.000/-0.002 in Head Height 1/2 in Key Type Bilateral Tensile Strength 64 000 psi System of Measurement Inch Key Shape Gib Head Height 5/16 in Width 5/16 in Rockwell Hardness B85 Features Tapers 1/8 in per ft Made in North America Yes Manufacturer Location Made in USA Pack Size Small Pack