Starrett hole saw arbor with pilot drill. Fits hole saws from 9/16-inch to 1-3/16-inch diameter. Arbor suitable for use with the New Fast Cut (FCH) and SH, DH, CT and KD hole saws (Diamond hole saw applications will usually require an arbor with a carbide tipped pilot drill). 11/32” Hex Shank Size. 1/2"-20 thread size. 3.1” drill length.