Fowler Outside Micrometer Fowler micrometers are of the finest quality available, at prices that defy competition. Special care in design and workmanship create a long lasting precision tool. Specifications include... 2-3" Measuring Range 0.0001" Graduations + .0002" Accuracy Features include... Ratchet Thimble Standard included Hammertone blue baked enamel finish. Microfine graduations on satin chrome finish and carbide tipped measuring faces. Diameter of measuring faces: .256" Flatness: .00003" Quick, easy zero adjustment on sleeve. Positive lever locking clamp Spindle thread hardened, ground and lapped for ultimate accuracy. Anvil & spindle hardened and precision ground with microlap finish on tips. Includes a wrench and case.