National Hardware 3-1/2" Square Oil Rubbed Bronze Spring Door Hinge is a high-quality, adjustable tension hinge designed for both residential and commercial applications. This Catalog model No. V520 series hinge features a durable cold-rolled steel construction and is listed for fire-rated openings, ensuring safety and reliability. Its closing speed can be easily adjusted to meet your specific needs, and it fits standard hinge cutouts with a stylish square corner design. for industrial, institutional, and home use, this spring door hinge combines functionality with a sleek oil-rubbed bronze finish that enhances any door. Model Number: N350-769