National Mfg N351-015 4 in Spring Adjustable Door Hinge Oil Rubbed

Product Description

The NATIONAL MFG/SPECTRUM BRANDS HHI N351-015 is a 4-inch spring adjustable door hinge finished in oil rubbed bronze. Manufactured from cold rolled steel, it is built for durability in both residential and light commercial door installations. The spring mechanism controls door closing automatically, with both closing speed and tension independently adjustable to suit the door weight and desired closing force. The hinge carries UL approval for fire door applications, making it suitable for code-required fire-rated assemblies. It fits standard hinge cutouts and features 5/8-inch radius round corners for a clean, conventional appearance.

This hinge is appropriate for standard interior and fire-rated door installations where a self-closing function is required by building code or occupant safety preference. It is commonly specified on fire-rated corridor doors, stairwell entries, and utility room doors in residential and light commercial construction. The adjustable closing speed and tension settings allow installers to fine-tune performance on site without replacing hardware. The oil rubbed bronze finish suits period and transitional door hardware sets. Each package contains two hinges.

Key Features

• Adjustable closing speed allows field tuning without additional tools or parts
• Adjustable tension accommodates varying door weights and closing force requirements
• UL approved for fire door applications, supporting code-compliant fire-rated assemblies
• Cold rolled steel construction provides strength and long-term durability
• Fits standard hinge cutouts for straightforward replacement or new installation
• 5/8-inch radius round corners match conventional door prep dimensions

Compatibility

Designed as an OEM-style replacement or upgrade hinge for standard 4-inch hinge cutout door preparations on residential and light commercial fire-rated and non-fire-rated doors.

Installation Notes

Installation is performed by carpenters, finish trades, or door hardware specialists following applicable building and fire codes. Power down or disable any electrified hardware in the door assembly before beginning work. Confirm that the door and frame prep matches the 4-inch hinge size and 5/8-inch radius corner profile before fastening. On fire-rated assemblies, verify that all hardware in the assembly, including hinges, latches, and closers, carries the appropriate UL or listing approval required by the authority having jurisdiction.