Mitutoyo's Granite Comparator Stands are basic building-blocks for the assembly of special-purpose, precision measuring equipment. By mounting precision measuring instruments such as Digimatic indicators, Mu-Checker Cartridge Heads, and Linear Gages onto the stands, it is possible to satisfy all manner of measuring assignment. The rigid granite base is free from burrs, pileups, rust, and deterioration over time. Specifications include... 6" x 8" x 2" Granite Base 1.181" Column Diameter 4.375" Throat Clearance 0.0001" Table Flatness Available with multiple height columns... 6", 8", 12", 18" Please select Column Height from pulldown menu.