This 28" X 36" (50.8cm x 61cm) Nylon Alpha Flag allows Boaters, Jet Skiers, and Watercraft Operators know that Divers are in the area and keep clear. The Alpha Flag is the True-International Diver-Down" Flag Recognized-Around-the-World as the Signal-to-Boaters that Divers-are-Below. If you have only the U.S. Traditional Red and White Striped Dive Flag on your Float or Boat, you should also carry this when Diving-Abroad. Flag has Brass Grommets for Easy Installation on a Pole.