SPECIFICATIONS FHA PIPE FLASHING #RJ15FHA 26 Gauge Galvanized Steel • For 1 ½ inch exhaust pipes 1 15⁄16 in. 2.38 cm HEIGHT 3 in. 7.62 cm 18 ½ in. 47 cm 16 in. 40.64 cm 7 ½ in. 19.05 cm 6 in. 6 in. 15.24 cm 15.24 cm 6 in. 15.