The double hook like this was used on the hall tree bench-furniture. This piece of furniture was in the entry hallway of the Victorian homes. The hooks, in sets of two or four, were usually placed around the mirror.
This cast-iron hook has four arms. The two upper arms extend 3 1/2 inches upward. They measure 4 3/4 inches apart. The hook projects approximately two inches from the surface. The hook merges with a bolt that is inserted into the front of the hall tree. Behind the hook is a neck piece (or spacer). From the back of the spacer to the end of the bolt is 1 1/16 inches. The hook is secured from the back of the piece of furniture with a nut.
This unusual, and very old, hook can be used anywhere now-a-days for a variety of reasons.