Iridium Mobile Magnet-Mount Antenna AT1621-12. This sale is for a Iridium Mobile Magnet-Mount Antenna AT1621-12. This Iridium Mobile magnet-mount Antenna delivers improved reception over the standard Portable Auxiliary Antenna. Built-in magnetic mount is used to secure the antenna to large metallic surfaces such as a vehicle rooftop. Diameter: 8.9 cm (3.5 in). Height: 2.2 cm (0.85 in). Weight: 405 g (14.3 oz). Operating Temperature: -40 to +70°C. Cable Type & Length: LMR-240, 16 feet (5 m). Antenna Connector: TNC Male. Polarization: Right hand circular. Axial Ratio: 15 dB Max. Radiation Coverage: 1.0 dB: Zenith to 40° 0.5 dB: 40° to 70° -0.5 dB: 70° to 80°. Part #: AT1621-12 (black), also known as SAF5340B.