Mitutoyo: 103-182 5-6" O/S Micrometer Enamelled Frame - Ratchet Thimble Economy type with carbide tipped anvils. Flatness: 0.6mm for up to 300mm (12"). 1.0mm for up to 300 - 500mm (12 - 20"). Parallelism: 2+L/100)mm (fraction rounded down).…View more