Micrometer Heads - Series 153 Metric models By M.T.I Qualos Share: Features Non rotating spindle Ratchet performs uniform and consistent force Tungsten Carbide tipped measuring faces Clear graduation on satin chrome finish Accuracy153-201/202 ± 3µm, 153-205/206 ± 0.00015 inches153-310 ± 1µm, 153-302 ± 0.00005 inches