{"product_id":"spi-29-558-4-class-zz-plus-plug-gage-0-558-inch","title":"Spi 29-558-4 Class Zz Plus Plug Gage 0.558 Inch","description":"\u003ch3\u003eProduct Description\u003c\/h3\u003e\n\u003cp\u003eThe SPI 29-558-4 is a Class ZZ Plus plug gage designed to verify the inside diameter of bored or reamed holes with a nominal size of 0.558 inches. It holds a tolerance of 0.0002 inches, making it suitable for go\/no-go inspection in production environments where consistent hole sizing is critical. Constructed from steel, this gage provides the hardness and wear resistance needed for repeat use on the shop floor. Machinists, toolmakers, and quality control technicians use Class ZZ plug gages as a fast, reliable method for dimensional verification without the need for electronic measurement equipment.\u003c\/p\u003e\n\u003cp\u003eThis gage is used in metalworking, machining, and precision manufacturing settings where hole diameter acceptance must be confirmed before assembly or further processing. It is well suited for inspecting drilled, reamed, or bored holes in steel, aluminum, and other common workpiece materials. The 0.558 inch nominal diameter fits a specific range of hole sizes where direct-contact gaging delivers faster throughput than CMM or air gaging in a high-volume inspection workflow.\u003c\/p\u003e\n\u003ch4\u003eKey Features\u003c\/h4\u003e\n\u003cul\u003e\n  \u003cli\u003e0.558 inch nominal diameter for direct hole inspection\u003c\/li\u003e\n  \u003cli\u003eClass ZZ Plus tolerance of 0.0002 inches for reliable go\/no-go results\u003c\/li\u003e\n  \u003cli\u003eSteel construction for durability and wear resistance in production use\u003c\/li\u003e\n  \u003cli\u003eCompact, lightweight design at 0.2 pounds for easy bench or floor use\u003c\/li\u003e\n  \u003cli\u003eSingle-piece package quantity — no minimum order beyond one unit\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch4\u003eCompatibility\u003c\/h4\u003e\n\u003cp\u003eDesigned as a standard Class ZZ Plus plug gage for use with any workpiece or fixture requiring verification of a 0.558 inch inside diameter hole to accepted go\/no-go inspection standards.\u003c\/p\u003e\n\u003ch4\u003eInstallation Notes\u003c\/h4\u003e\n\u003cp\u003ePlug gages are handled and applied by machinists or quality inspectors — no power source or lockout procedure is required. Ensure the workpiece is clean and free of burrs or chips before gaging to avoid false readings or gage wear. Handle the gage with clean, dry hands or inspection gloves to prevent corrosion from skin contact. Store in a protective case away from other tooling to preserve the gaging surface and tolerance integrity.\u003c\/p\u003e\n\u003ch4\u003eTechnical Specifications\u003c\/h4\u003e\n\u003cul\u003e\n  \u003cli\u003e\n\u003cstrong\u003eGage Class\u003c\/strong\u003e: ZZ Plus\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eNominal Diameter\u003c\/strong\u003e: 0.558 inches\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eTolerance\u003c\/strong\u003e: 0.0002 inches (0.0002 mm)\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eMaterial\u003c\/strong\u003e: Steel\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eWeight\u003c\/strong\u003e: 0.2 pounds\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch4\u003eStandard Information\u003c\/h4\u003e\n\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: 29-558-4\u003c\/li\u003e\n\u003c\/ul\u003e","brand":"SPIROTHERM","offers":[{"title":"Default Title","offer_id":51722056499506,"sku":"29-558-4","price":14.99,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0270\/4519\/9983\/files\/39c6b10ba8c13e9330bd8b05ba4b1636.jpg?v=1788584867","url":"https:\/\/voomisupply.com\/products\/spi-29-558-4-class-zz-plus-plug-gage-0-558-inch","provider":"Voomi Supply","version":"1.0","type":"link"}