468-163 Mitutoyo Holtest 10-12mmMitutoyo Digimatic Holtest 3 Point Internal Micrometer Specifications include 10 12mm Measuring Range 0. 001mm Resolution 2um Accuracy Features include TiN coated contact points provide excellent durability, impact resistance, and allow the instrument to measure right to the bottom of a blind hole. Large LCD readout. With Ratchet Stop for constant force. Measurement can be taken closer to the bottom of the blind bore. Can measure deep holes by