{"product_id":"spi-13-453-6-combination-square-blade-12-inches-4r","title":"Spi 13-453-6 Combination Square Blade 12 Inches 4R","description":"\u003ch3\u003eProduct Description\u003c\/h3\u003e\u003cp\u003eThe SPI 13-453-6 is a 12-inch replacement blade for 4R combination squares, designed for layout and inspection work in trades where precise measurement is critical. The blade features a baked enamel coating that protects the graduated markings from wear and corrosion during regular shop or field use. Four graduation increments are scribed into the blade: 1\/64 inch, 1\/32 inch, 1\/16 inch, and 1\/8 inch. This range of divisions supports fine layout work alongside quick coarse measurements without switching tools. Machinists, pipefitters, sheet metal workers, and general tradespeople install this blade as a direct replacement in compatible 4R combination square heads.\u003c\/p\u003e\u003cp\u003eThis blade is suited for residential and commercial trade environments where a combination square is a daily-use layout tool. Typical applications include marking cut lines on pipe, conduit, sheet metal, lumber, and structural steel. The 12-inch length provides adequate reach for layout on standard framing members and mechanical components. The graduated markings on both sides of the blade allow readings from either orientation, which is useful in confined installation spaces.\u003c\/p\u003e\u003ch4\u003eKey Features\u003c\/h4\u003e\u003cul\u003e\n\u003cli\u003e12-inch blade length for standard combination square compatibility\u003c\/li\u003e\n\u003cli\u003e4R graduation pattern with four increment divisions: 1\/64, 1\/32, 1\/16, and 1\/8 inch\u003c\/li\u003e\n\u003cli\u003eBaked enamel finish protects markings from abrasion and light corrosion\u003c\/li\u003e\n\u003cli\u003eSingle-piece blade sold individually, suitable for field replacement\u003c\/li\u003e\n\u003cli\u003eGraduated markings support both fine layout and general measurement tasks\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch4\u003eCompatibility\u003c\/h4\u003e\u003cp\u003eDesigned as an OEM-style replacement blade for 4R combination squares accepting a standard 12-inch blade.\u003c\/p\u003e\u003ch4\u003eInstallation Notes\u003c\/h4\u003e\u003cp\u003eBlade replacement on a combination square is performed by loosening the locking fastener on the square head and sliding the worn blade out. Slide the replacement blade into the head channel and retighten the locking fastener to secure it before use. No specialized tools or trade licensing are required for this swap. Verify the blade is fully seated and the lock is firm before taking any measurement or marking cut lines.\u003c\/p\u003e\u003ch4\u003eTechnical Specifications\u003c\/h4\u003e\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eBlade Length\u003c\/strong\u003e: 12 inches\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eGraduation Type\u003c\/strong\u003e: 4R\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eGraduation Increments\u003c\/strong\u003e: 1\/64 inch, 1\/32 inch, 1\/16 inch, 1\/8 inch\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eFinish\u003c\/strong\u003e: Baked Enamel\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eWeight\u003c\/strong\u003e: 0.25 pounds\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003ePackage Quantity\u003c\/strong\u003e: 1\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: 13-453-6\u003c\/li\u003e\n\u003c\/ul\u003e","brand":"SPIROTHERM","offers":[{"title":"Default Title","offer_id":51693810352434,"sku":"13-453-6","price":51.12,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0270\/4519\/9983\/files\/634cc6dc04fbefe531670b7f2b92e2de.jpg?v=1788317652","url":"https:\/\/voomisupply.com\/products\/spi-13-453-6-combination-square-blade-12-inches-4r","provider":"Voomi Supply","version":"1.0","type":"link"}