{"product_id":"gibraltar-kn-31ss-g-round-knurled-check-nut-5-16-18-unc","title":"Gibraltar KN-31SS-G Round Knurled Check Nut 5\/16-18 Unc","description":"\u003ch3\u003eProduct Description\u003c\/h3\u003e\u003cp\u003eThe GIBRALTAR KN-31SS-G is a stainless steel round knurled check nut designed for 5\/16-18 UNC threaded applications. Check nuts, also called jam nuts or lock nuts, thread down against a primary nut or fitting to prevent loosening under vibration, thermal cycling, or mechanical load. This unit features a knurled round head for improved grip during hand-tightening and tool-assisted installation. The uncoated stainless steel construction resists corrosion in wet, chemical, or outdoor environments. The overall height is 3\/8 inches, with a 1-inch head diameter, a base diameter of 3\/4 inches, and a base height of 3\/32 inches. The part weighs 0.06 pounds. Licensed trades and mechanical contractors specify stainless fasteners like this one where mild steel hardware would corrode or fail inspection.\u003c\/p\u003e\u003cp\u003eThis check nut suits residential and light commercial mechanical installations where a 5\/16-18 UNC thread is present and a secondary locking fastener is required. Typical applications include HVAC equipment mounting, plumbing fixture hardware, pump assemblies, and general mechanical panel or enclosure work. The knurled head profile makes it practical in confined spaces where a wrench may not seat fully but hand torque plus tool snugging is sufficient. Sold individually, it is suitable for single-point repairs or small-batch installations without requiring a bulk purchase.\u003c\/p\u003e\u003ch4\u003eKey Features\u003c\/h4\u003e\u003cul\u003e\n\u003cli\u003e5\/16-18 UNC thread for compatibility with standard inch-series fastener systems\u003c\/li\u003e\n\u003cli\u003eRound knurled head allows hand-tightening and positive grip without a specialty tool\u003c\/li\u003e\n\u003cli\u003eUncoated stainless steel construction resists corrosion in wet or chemically active environments\u003c\/li\u003e\n\u003cli\u003eLow-profile check nut design seats against a primary nut or fitting surface to prevent loosening\u003c\/li\u003e\n\u003cli\u003e1-inch head diameter and 3\/8-inch overall height suit tight clearance installations\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch4\u003eCompatibility\u003c\/h4\u003e\u003cp\u003eDesigned as an OEM-style replacement or service fastener for mechanical assemblies requiring a 5\/16-18 UNC threaded check nut in stainless steel.\u003c\/p\u003e\u003ch4\u003eInstallation Notes\u003c\/h4\u003e\u003cp\u003eInstallation is performed by licensed mechanical, HVAC, or plumbing technicians as part of broader equipment service or assembly work. Thread the check nut onto the stud or bolt until it seats firmly against the primary nut or fitting face, then snug with an appropriately sized wrench. De-energize and isolate any equipment before accessing fastener locations inside live panels or pressurized assemblies. Do not overtighten stainless fasteners, as galling can occur on stainless-to-stainless thread contact without anti-seize compound.\u003c\/p\u003e\u003ch4\u003eTechnical Specifications\u003c\/h4\u003e\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eThread Size\u003c\/strong\u003e: 5\/16-18\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eThread Standard\u003c\/strong\u003e: UNC\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eNut Type\u003c\/strong\u003e: Check Nut\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eHead Type\u003c\/strong\u003e: Round Knurled\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eMaterial\u003c\/strong\u003e: Stainless Steel\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eFinish\u003c\/strong\u003e: Uncoated\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eHead Diameter\u003c\/strong\u003e: 1 inch\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eOverall Height\u003c\/strong\u003e: 3\/8 inches\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eBase Diameter\u003c\/strong\u003e: 3\/4 inches\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eBase Height\u003c\/strong\u003e: 3\/32 inches\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eWeight\u003c\/strong\u003e: 0.06 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: GIBRALTAR\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eManufacturer Part Number\u003c\/strong\u003e: KN-31SS-G\u003c\/li\u003e\n\u003c\/ul\u003e","brand":"GIBRALTAR","offers":[{"title":"Default Title","offer_id":51708939272498,"sku":"KN-31SS-G","price":25.87,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0270\/4519\/9983\/files\/2508f519cf61d6fc183f3f8b48b1ca57.jpg?v=1788449190","url":"https:\/\/voomisupply.com\/products\/gibraltar-kn-31ss-g-round-knurled-check-nut-5-16-18-unc","provider":"Voomi Supply","version":"1.0","type":"link"}