{"product_id":"spi-21-261-3-flat-button-contact-point-2-1-2-in-dial","title":"Spi 21-261-3 Flat Button Contact Point 2-1\/2 in Dial","description":"\u003ch3\u003eProduct Description\u003c\/h3\u003e\u003cp\u003eThe SPI 21-261-3 is a flat button contact point designed for use with dial indicators. Machined from black oxide steel, this AGD Group 1 contact point features a 4-48 thread size for secure attachment to compatible indicator spindles. It measures 2.5 inches in diameter with a contact point length of 0.25 inches. The flat button profile is suited for surface measurement applications where a broad, stable contact face is needed. Metrology technicians, machinists, and quality control professionals install this type of contact point when swapping out worn tips or adapting an indicator to a specific measurement task.\u003c\/p\u003e\u003cp\u003eThis contact point is intended for use with dial indicators in precision measurement settings, including machine shop environments, inspection stations, and dimensional verification setups. The flat button style is commonly selected for measuring flat or near-flat surfaces where a spherical or pointed tip would produce less reliable readings. Its AGD Group 1 designation indicates compatibility with standard AGD-spec dial indicator spindles.\u003c\/p\u003e\u003ch4\u003eKey Features\u003c\/h4\u003e\u003cul\u003e\n\u003cli\u003eFlat button contact face provides stable, broad surface contact for flat-surface measurement\u003c\/li\u003e\n\u003cli\u003eBlack oxide steel construction for durability and corrosion resistance\u003c\/li\u003e\n\u003cli\u003e4-48 thread size for secure spindle attachment\u003c\/li\u003e\n\u003cli\u003e2.5 inch diameter contact point head\u003c\/li\u003e\n\u003cli\u003eContact point length of 0.25 inches\u003c\/li\u003e\n\u003cli\u003eAGD Group 1 designation for compatibility with standard dial indicator spindles\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch4\u003eCompatibility\u003c\/h4\u003e\u003cp\u003eDesigned for use with dial indicators. AGD Group 1 industry designation applies to standard AGD-spec dial indicator spindles accepting a 4-48 threaded contact point.\u003c\/p\u003e\u003ch4\u003eInstallation Notes\u003c\/h4\u003e\u003cp\u003eContact point replacement is typically performed by machinists or metrology technicians using standard hand tools. Before swapping contact points, remove the indicator from any active fixture and ensure no load is applied to the spindle. Thread the contact point carefully by hand first to avoid cross-threading the 4-48 spindle thread, then snug with the appropriate tool without overtightening.\u003c\/p\u003e\u003ch4\u003eTechnical Specifications\u003c\/h4\u003e\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eThread Size\u003c\/strong\u003e: 4-48\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eContact Point Style\u003c\/strong\u003e: Flat Button\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eContact Point Length\u003c\/strong\u003e: 0.25 inches\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eDiameter\u003c\/strong\u003e: 2.5 inches\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003ePoint Material\u003c\/strong\u003e: Black Oxide Steel\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eIndustry Designation\u003c\/strong\u003e: AGD Group 1\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eFor Use With\u003c\/strong\u003e: Dial Indicators\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eWeight\u003c\/strong\u003e: 0.1 pounds\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch4\u003eStandard Information\u003c\/h4\u003e\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eBrand\u003c\/strong\u003e: SPI\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eManufacturer Part Number\u003c\/strong\u003e: 21-261-3\u003c\/li\u003e\n\u003c\/ul\u003e","brand":"SPIROTHERM","offers":[{"title":"Default Title","offer_id":67648946012466,"sku":"21-261-3","price":34.5,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0270\/4519\/9983\/files\/9fc90b365d7691ed336341b0c7cf92fb.jpg?v=1790460831","url":"https:\/\/voomisupply.com\/products\/spi-21-261-3-flat-button-contact-point-2-1-2-in-dial","provider":"Voomi Supply","version":"1.0","type":"link"}