The GB3-1 is a Galvanized Base with Neoprene Collar. The FAMCO GB3-1 is made to fit 1 ¼“, 1 ½ “, 2” and 3” PVC vent pipe. The GBN model fits any roof pitch from flat to 45 degrees. This product is fully tested for ultraviolet, ozone and weather resistance. Available in black, brown, gray and Galvanized Steel.