Designed for Roof, Wall or Deck Antenna Dish Installations. Base Mount Hole Spacing: 5" x 7 7/8" (centers) For use with 100 - 120 cm Satellite Dishes, and Large Directional HD TV Antennas Aerials Satellite Dish Mount with 2" OD SuperDMount Universal 28" J Pipe/Tower mount with 2" OD mount for adding large off-air antennas and satellite dish systems. Can be used on side of house or roof with large mount foot for improved stability. Galvanized steel, 28 inches long, 2" OD, E-Coated for maximum protection. If you need the extra length we have got it.