Fence Bracket For 18" High Signs (With 2 Bolts & 2 Nuts) - By SmartSign DURABLE. Brackets are rugged and are made from 14-gauge steel with a baked enamel finish to prevent rust. COMPATIBLE. Brackets are great for chain-link fences of all sizes and fit 18" tall signs, including 18" x 12", 18" x 18" (circle, square, and octagon) and 18" x 24" signs. EASY TO INSTALL. Screw the bracket's bolts through your sign and fasten on the back side of the fence. Brackets include 4 mounting holes. The inner set is 12" apart and the outer set is 15" apart.