National Mfg N350-892 Spring Adjustable Door Hinge 3.5 in

Product Description

The NATIONAL MFG/SPECTRUM BRANDS HHI N350-892 is a 3.5-inch spring adjustable door hinge finished in satin nickel. Manufactured from cold rolled steel, this hinge provides durable performance in both residential and light commercial door applications. The integrated spring mechanism controls door closing action, with both closing speed and tension independently adjustable to suit a wide range of door weights and swing frequencies. Corner radius measures 5/8 inches, fitting standard hinge cutout dimensions without modification. The hinge carries UL listing for use on fire-rated doors, making it suitable for code-compliant installations where self-closing hardware is required. Sold in a package of two. Installation is performed by a qualified carpenter, contractor, or door hardware professional.

This hinge is designed for standard interior and fire-rated door applications where a self-closing, adjustable spring hinge is required. The satin nickel finish suits modern and transitional door hardware sets. Its adjustable closing speed and tension make it adaptable across a variety of door weights and swing conditions. The UL approval for fire doors allows use in locations where building codes mandate self-closing door assemblies, such as stairwells, utility rooms, and corridor doors in residential and light commercial construction.

Key Features

• Closing speed is field-adjustable to control door swing rate
• Spring tension is independently adjustable for door weight compatibility
• Fits standard hinge cutout — no door or frame modification required
• 5/8-inch radius round corners for clean fitment in existing mortises
• UL approved for use on fire-rated doors
• Cold rolled steel construction for durability
• Satin nickel finish for corrosion resistance and aesthetic compatibility

Compatibility

Designed as an OEM-style replacement or new-installation spring hinge for standard residential and light commercial doors with a 3.5-inch hinge cutout, including UL-listed fire-rated door assemblies.

Installation Notes

Installation is typically performed by a door hardware technician, finish carpenter, or licensed contractor. Remove the existing hinge and verify the mortise dimensions match the 3.5-inch leaf size before installation. Adjust closing speed and tension using the manufacturer adjustment points after the door is hung and hardware is fully fastened. On fire-rated assemblies, confirm the complete door and frame assembly meets the applicable fire door code requirements before returning the door to service.