Stone Harbor Hardware's radius corner adjustable spring hinges are an excellent alternative to more expensive overhead closers that can be used on fire doors, hotel room doors, and apartment interior doors. This product is sold individually as one spring hinge. These UL-rated hinges measure 3-1/2 inches by 3-1/2 inches and meet the NFPA80 standard for 3-hour fire doors. All of the necessary mounting hardware, consisting of #9 x 3/4" wood screws, is included for a hassle-free installation. Stone Harbor Hardware products are manufactured with durable materials to create a long-lasting and high-quality product that matches other Stone Harbor Hardware items of the same finish. 1/4" - The sides of our 1/4" radius corner hinges form a delicate curve that matches the shape of a dime. 5/8" - The sides of our 5/8" radius corner hinges form a broad curve that matches the shape of a quarter.
