Fowler 250-275mm Outside Metric Micrometer 52-248-011-1 Series No. 52-248 offers Fowler standards of fine quality and accuracy. A variety of sizes covers a range of measuring applications. Hammertone blue baked enamel finish Microfine graduations on satin chrome finish and carbide tipped measuring faces Diameter of measuring faces: 6.5mm Ratchet stop thimble for exact and repetitive readings Spindle thread is hardened, ground and lapped Anvil & spindle hardened and precision ground with microlap finish on tips All micrometers meet or exceed U.S. Federal specifications for accuracy Includes a wrench and case