Dasqua 20-50mm Digital inside micrometer set. Resolution is .00005"/ .001mm. Strictly made in accordance with DIN863. Hold function. Large, easy-to-read digital display. Self-centering micrometer with a hardened head. Carbide measuring jaws for accurate & true measurement of internal diameters. Extension provided for deeper measuring. Setting rings for adjustments are included in all sets . Ratchet stop provides correct contact pressure for accurate readings. Contact points are designed for measurements near the bottom of blind holes. Includes instant inch/millimeter conversion. Furnished in fitted case.