{"product_id":"national-marker-n351015-spring-door-hinge-4-in","title":"National Marker N351015 Spring Door Hinge 4 In.","description":"\u003ch3\u003eProduct Description\u003c\/h3\u003e\n\u003cp\u003eThe NATIONAL MARKER N351015 is a 4-inch spring door hinge finished in oil rubbed bronze, designed for standard residential and light commercial door installations. Built from cold-rolled steel, this hinge provides durable, consistent self-closing performance on hinged doors. The closing speed and tension are both field-adjustable, allowing installers to dial in the right action for the door weight and traffic level. The 5\/8-inch radius corner profile fits standard hinge cutouts without modification. It carries UL approval for use on fire-rated doors, making it suitable for applications where code compliance is required.\u003c\/p\u003e\n\u003cp\u003eThis spring hinge is used in residential and light commercial settings where self-closing doors are required by code or building specification. Common applications include fire-rated corridor doors, utility room entries, and access doors in commercial tenant spaces. Its standard cutout compatibility makes it a straightforward drop-in replacement during door hardware service or new construction installs.\u003c\/p\u003e\n\u003ch4\u003eKey Features\u003c\/h4\u003e\n\u003cul\u003e\n  \u003cli\u003eAdjustable closing speed for field-tuned door action\u003c\/li\u003e\n  \u003cli\u003eAdjustable tension to accommodate varying door weights\u003c\/li\u003e\n  \u003cli\u003eCold-rolled steel construction for long-term durability\u003c\/li\u003e\n  \u003cli\u003e5\/8-inch radius corners fit standard hinge cutouts without modification\u003c\/li\u003e\n  \u003cli\u003eUL approved for fire-rated door applications\u003c\/li\u003e\n  \u003cli\u003eOil rubbed bronze finish for consistent appearance on period or transitional hardware sets\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch4\u003eCompatibility\u003c\/h4\u003e\n\u003cp\u003eDesigned as an OEM-style replacement spring hinge for standard door hinge cutouts on residential and light commercial hinged doors. Cataloged as National model V522.\u003c\/p\u003e\n\u003ch4\u003eInstallation Notes\u003c\/h4\u003e\n\u003cp\u003eInstallation is typically performed by a carpenter, general contractor, or door hardware technician. Before installation, confirm the door is properly hung and the existing hinge mortise matches the 4-inch leaf size. Tension and closing speed adjustments should be made with the door in place using the manufacturer-provided adjustment tool or a compatible hex wrench. On fire-rated assemblies, verify the completed installation meets the requirements of the applicable fire door assembly listing and local building code.\u003c\/p\u003e\n\u003ch4\u003eTechnical Specifications\u003c\/h4\u003e\n\u003cul\u003e\n  \u003cli\u003e\n\u003cstrong\u003eHinge Size\u003c\/strong\u003e: 4 inches\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eCorner Radius\u003c\/strong\u003e: 5\/8 inches\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eFinish\u003c\/strong\u003e: Oil Rubbed Bronze\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eMaterial\u003c\/strong\u003e: Cold-Rolled Steel\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eClosing Speed\u003c\/strong\u003e: Adjustable\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eTension\u003c\/strong\u003e: Adjustable\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eCertification\u003c\/strong\u003e: UL Approved for Fire Doors\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eWeight\u003c\/strong\u003e: 0.877 pounds\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eSold As\u003c\/strong\u003e: Each\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: NATIONAL MARKER\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eManufacturer Part Number\u003c\/strong\u003e: N351015\u003c\/li\u003e\n\u003c\/ul\u003e","brand":"NATIONAL MARKER","offers":[{"title":"Default Title","offer_id":51346824331570,"sku":"N351015","price":31.65,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0270\/4519\/9983\/files\/310550659.jpg?v=1782091515","url":"https:\/\/voomisupply.com\/products\/national-marker-n351015-spring-door-hinge-4-in","provider":"Voomi Supply","version":"1.0","type":"link"}