{"product_id":"starrett-63491-mechanical-outside-micrometer-3-in-range","title":"Starrett 63491 Mechanical Outside Micrometer 3 in Range","description":"\u003ch3\u003eProduct Description\u003c\/h3\u003e\u003cp\u003eThe STARRETT 63491 is a mechanical outside micrometer with a 3-inch measurement range and a graduation of 0.0001 inches, delivering accuracy to 0.000050 inches. It features a ratchet stop thimble for consistent, repeatable measuring force and a ring-style lock nut to secure the spindle position once a measurement is taken. The measuring faces and anvil are made from solid carbide, providing exceptional wear resistance during frequent use. A digital counter is integrated for easy reading, and the one-piece spindle design is engineered for long-term dimensional stability. This tool is suited for precision measurement tasks in fabrication shops, machine shops, and field service environments.\u003c\/p\u003e\u003cp\u003eThe STARRETT 63491 is designed for trade professionals who require tight-tolerance outside measurements across a range of 0 to 3 inches. Typical applications include measuring shaft diameters, wall thicknesses, and machined component dimensions. It is appropriate for use in HVAC equipment manufacturing, plumbing component fabrication, electrical enclosure work, and general mechanical trades where dimensional accuracy is critical. The included lock nut and wrench allow secure adjustment and calibration in the field or shop.\u003c\/p\u003e\u003ch4\u003eKey Features\u003c\/h4\u003e\u003cul\u003e\n\u003cli\u003eMeasurement range of 0 to 3 inches with 0.0001-inch graduation\u003c\/li\u003e\n\u003cli\u003eAccuracy to 0.000050 inches for tight-tolerance work\u003c\/li\u003e\n\u003cli\u003eSolid carbide measuring faces and anvil for extended wear life\u003c\/li\u003e\n\u003cli\u003eRatchet stop thimble ensures consistent measuring force\u003c\/li\u003e\n\u003cli\u003eIntegrated digital counter for fast, clear readings\u003c\/li\u003e\n\u003cli\u003eExtremely hard and stable one-piece spindle construction\u003c\/li\u003e\n\u003cli\u003eRing-style lock nut included with wrench for field calibration\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch4\u003eCompatibility\u003c\/h4\u003e\u003cp\u003eDesigned as a general-purpose outside micrometer suitable for precision measurement tasks in mechanical, fabrication, and trade service applications.\u003c\/p\u003e\u003ch4\u003eInstallation Notes\u003c\/h4\u003e\u003cp\u003eThis instrument requires no installation but should be zeroed and verified against a calibration standard before use. Store the micrometer with the anvil and spindle faces slightly separated to prevent damage from thermal expansion. Clean measuring faces with a lint-free cloth before each use to ensure accurate readings. Calibration and maintenance should be performed by a qualified metrologist or per shop quality procedures.\u003c\/p\u003e\u003ch4\u003eTechnical Specifications\u003c\/h4\u003e\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eMaximum Measurement Range\u003c\/strong\u003e: 3 inches\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eGraduation\u003c\/strong\u003e: 0.0001 inches\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eAccuracy\u003c\/strong\u003e: 0.000050 inches\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eThimble Type\u003c\/strong\u003e: Ratchet Stop\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eAnvil Type\u003c\/strong\u003e: Flat\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eAnvil Diameter\u003c\/strong\u003e: 0.2500 inches (6.35 mm)\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eSpindle Diameter\u003c\/strong\u003e: 0.2500 inches (6.35 mm)\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eMeasuring Face Material\u003c\/strong\u003e: Solid Carbide\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eLock Nut Type\u003c\/strong\u003e: Ring\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eDigital Counter\u003c\/strong\u003e: Yes\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eRotating Spindle\u003c\/strong\u003e: No\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eCoating\/Finish\u003c\/strong\u003e: Satin\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eIncludes\u003c\/strong\u003e: Lock Nut, Wrench\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eWeight\u003c\/strong\u003e: 1.3 pounds\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eStandards\u003c\/strong\u003e: California Proposition 65\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch4\u003eStandard Information\u003c\/h4\u003e\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eBrand\u003c\/strong\u003e: STARRETT\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eManufacturer Part Number\u003c\/strong\u003e: 63491\u003c\/li\u003e\n\u003c\/ul\u003e","brand":"STARRETT","offers":[{"title":"Default Title","offer_id":51543394386226,"sku":"63491","price":581.87,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0270\/4519\/9983\/files\/e8d8aaafd96227c22b762bb89bda919a.jpg?v=1785917812","url":"https:\/\/voomisupply.com\/products\/starrett-63491-mechanical-outside-micrometer-3-in-range","provider":"Voomi Supply","version":"1.0","type":"link"}