All ALP Series antennas are constructed of 1/8” FR4 fiberglass board and are extremely rugged. The ALP620 and ALP650L/E antennas are best suited for portable applications including temporary setups for field shoots, while the more economical ALP500 is well-suited for more permanent indoor installation. Additionally, the perforated design of the ALP620 makes it highly resistant to wind loading. None of the antennas in the ALP Series are intended to be left outdoors indefinitely. A sturdy aluminum housing protects the 50 Ohm BNC connector on the ALP620 and ALP650 models.