Finish:Lifetime Brass (PVD) Baldwin"s "S" Door Knocker is forged in solid brass and available in a wide variety of quality finishes; see options to select. Ships with fasteners suitable for 1"-thick door.Base mount diameter: 2"Center-to-center of bolts: 4"Projection: 2"Note: Product finishes which are RELIEVED may vary in luster, hue, and appearance as a result of handcrafted variances in the final finishing step.