Allen Nut, System of Measurement Inch, Insert Diameter 1/2 in, Overall Length 33/64 in, Installed Length Not Applicable, Thread Size M8-1.25, Thread Direction Right Hand, Thread Type Coarse, Flange Diameter Not Applicable, Flange Thickness Not Applicable, Material Steel, Material Grade/Class Grade 2H, Finish Black Oxide, Body Texture Knurled, Compatible Material Metal, Drill Bit Size 33/64 in, Maximum Hole Diameter 0.516 in, Minimum Material Thickness 0.522 in