Mitutoyo Screw Thread Micrometer Interchangeable Anvil Type Micrometer Specifications include... 25-50mm Measuring Range 0.01mm Graduations + 4um Accuracy Features include... For use with 55° or 60° interchangeable anvils Ratchet Stop Supplied in fitted case Interchangeable Anvils Sold Separately 55° Anvils: # 126-810 60° Anvils: # 126-800