Built to take advantage of the GLONASS system/constellation of satellites as well as standard GPS, this robust external antenna is packaged in a low-profile waterproof housing and provides 3 easy mounting solutions: pole, surface or under-deck (for the underside of fiberglass decks).\n\nExternal GPS/GLONASS antennas provide increased flexibility and installation options as well as the potential for enhanced reception of GPS/GLONASS signal for those products with built-in GPS/GLONASS antennas.