High Quality Pair of Matte (Flat) Black 4 x 4 inches with 5/8 inch Square radius. Black Adjustable Spring Hinges. Includes matching screws, 4 hole zig-zag pattern, gauge .106" (2.7MM). Typical use: 1 5/8" - 1 3/4" thick doors. Also known as self-closing hinges or door closing hinges.