Piano hinges, also known as a continuous hinge, were originally designed to evenly distribute the weight of a piano lid and reduce strain on other parts regardless of where it is lifted. Today they are also used for chests, bench lids, cabinets or wherever you need a 6' hinge. Constructed of heavy gauge steel with a durable plated finish of your choice these hinges add strength and stability. They can be installed to conceal the underside of back of an object. 2" hole spacing x 1/2" knuckle length. Mounting hardware is included.