National Hardware 3-1/2" Oil Rubbed Bronze 1/4" Radius Spring Door Hinge is a durable and reliable door hinge designed for self-closing doors in various settings such as basements, stairways, garages, and entrances. Made from cold-rolled steel, this hinge is suitable for residential, commercial, and apartment buildings. It features a 1/4" radius with round corners and is UL for fire doors, ensuring safety and compliance. The closing speed of the hinge is adjustable, allowing for customized door operation, and it fits standard hinge cutouts for easy installation. Model Number: N350-827