Mitutoyo Hub Micrometer The Mitutoyo 147 series hub micrometer has a shallow-throated frame for measuring hub thickness and shoulders inside a bore, and a vernier scale in inch units for taking precise outside diameter (OD) measurements. It also has a ratchet-stop mechanism for uniform pressure during adjustment. The micrometer has a baked enamel finish for protection and durability of frame. The vernier scale on the thimble and sleeve is graduated to 0.001", and has a satin chrome rust- and glare-resistant finish. The spindle and anvil have flat measuring faces and are carbide-tipped for wear resistance. The micrometer comes with a plastic case for storage. Specifications includes... 2-3" Measuring Range 0.001" Graduations +0.0001" Accuracy Features include... Shallow-throated frame for measuring hub thickness and shoulders inside a bore Vernier scale in inch units for taking precise outside diameter (OD) measurements Ratchet-stop mechanism helps provide uniform pressure for precise, repeatable measurement Satin chrome finish on thimble and sleeve helps resist rust and reduce glare Carbide facing on spindle and anvil provides wear resistance