Features This is the Starrett mechanical digital micrometer - simple to use even by the inexperienced Clear, easily read numbers reduce errors Balanced frame design for comfortable and accurate measuring Gracefully designed tapered frame for use in narrow slots and tight places Carbide Measuring Faces Micro-lapped measuring faces Starrett no-glare satin chrome finish on thimble and sleeve No-glare black finish on the frame Ring-type knurled lock nut for quick and sure locking The anvil and spindle are sized at .250" (6.35mm) Extremely hard and stable one-piece spindle .001" or .01mm is read directly from the counter .0001" or .001mm is read from the vernier scale on the micrometer sleeve Specifications Made in America: Yes Micrometer Type: Outside Range (mm): 150-175mm Graduations (mm): 0.01mm Anvil/Spindle Material: Carbide Anvil Type: Flat Spindle Type: Flat Lock Nut Type: Knurled Ring Type Thimble Type: Ratchet Accuracy (mm): +/-.005mm