Whiteside UD5122M Spiral Up / Downcut Router Bit. Also known as a 2 + 2 Compression bit, this router bit's combination up and down cut design eliminates chipping when trimming double sided laminates and veneers. Bit has an up cut end for mortising type work. Double fluted spiral profile makes the smoothest of cuts. Solid carbide. Whiteside Machine Company - Claremont, North Carolina. Specifications SH = Shank Size. CD = Cutting Diameter. CL = Cutting Length. OAL = Overall Length. 1/2" SH x 1/2" CD x 1-1/4" CL x 3" OAL Model: UD5122M