{"product_id":"starrett-72739-outside-micrometer-12-in-ratchet-stop","title":"Starrett 72739 Outside Micrometer 12 in Ratchet Stop","description":"\u003ch3\u003eProduct Description\u003c\/h3\u003e\u003cp\u003eThe STARRETT 72739 is a mechanical outside micrometer with a 12-inch maximum measurement range and a graduation of 0.0001 inches, delivering an accuracy of 0.0002 inches. It features a ratchet stop thimble for consistent measuring pressure and a satin chrome finish that reduces glare during use. The measuring faces use solid carbide inserts on both the anvil and spindle, extending service life in high-cycle shop environments. A ring-style lock nut secures the spindle position once a measurement is taken. This instrument is used by machinists, tool and die makers, quality control technicians, and precision fabricators who require reliable large-range outside diameter or thickness measurement.\u003c\/p\u003e\u003cp\u003eThe 72739 suits applications requiring accurate outside measurement of large workpieces up to 12 inches. Typical use cases include checking large-diameter shafts, structural stock thickness, and precision-machined components in manufacturing, tooling, and inspection departments. The flat anvil geometry accommodates a wide range of part profiles. Both the anvil and spindle diameters measure 0.3 inches (7.60 mm), providing a defined contact area. This micrometer is supplied with a lock nut and a wrench. Starrett number T436XRL-12 is the OEM reference for this instrument.\u003c\/p\u003e\u003ch4\u003eKey Features\u003c\/h4\u003e\u003cul\u003e\n\u003cli\u003e12-inch maximum measurement range for large-workpiece inspection\u003c\/li\u003e\n\u003cli\u003e0.0001-inch graduation with 0.0002-inch accuracy\u003c\/li\u003e\n\u003cli\u003eRatchet stop thimble ensures repeatable measuring force\u003c\/li\u003e\n\u003cli\u003eSolid carbide measuring faces on both anvil and spindle for extended wear life\u003c\/li\u003e\n\u003cli\u003eRing-style lock nut holds spindle position during reading or transfer\u003c\/li\u003e\n\u003cli\u003eSatin chrome finish reduces glare under shop lighting\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch4\u003eCompatibility\u003c\/h4\u003e\u003cp\u003eDesigned as a direct-use mechanical outside micrometer for large-range dimensional inspection tasks. Refer to Starrett number T436XRL-12 for OEM cross-reference.\u003c\/p\u003e\u003ch4\u003eInstallation Notes\u003c\/h4\u003e\u003cp\u003eOutside micrometers require no installation, but should be calibrated against a certified standard or gauge block stack before use, particularly after transport or storage. Store in the supplied case or a clean, padded location away from temperature extremes to preserve accuracy. Clean the measuring faces with a lint-free cloth before and after each use. Never force the thimble against a workpiece — allow the ratchet stop to control contact pressure.\u003c\/p\u003e\u003ch4\u003eTechnical Specifications\u003c\/h4\u003e\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eMaximum Measurement Range\u003c\/strong\u003e: 12 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: 0.0002 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\u003eMeasuring Face Material\u003c\/strong\u003e: Solid Carbide\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eAnvil Diameter\u003c\/strong\u003e: 0.3 inches (7.60 mm)\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eSpindle Diameter\u003c\/strong\u003e: 0.3 inches (7.60 mm)\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eLock Nut Type\u003c\/strong\u003e: Ring\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eFinish\u003c\/strong\u003e: Satin Chrome\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: 3 pounds\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eStarrett Number\u003c\/strong\u003e: T436XRL-12\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: 72739\u003c\/li\u003e\n\u003c\/ul\u003e","brand":"STARRETT","offers":[{"title":"Default Title","offer_id":51542505193778,"sku":"72739","price":619.54,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0270\/4519\/9983\/files\/889b304adc6de59781b62bdf8cba3c3b.jpg?v=1785902267","url":"https:\/\/voomisupply.com\/products\/starrett-72739-outside-micrometer-12-in-ratchet-stop","provider":"Voomi Supply","version":"1.0","type":"link"}