Maxtena M1621HCT Iridium Certified Antennas are built on proprietary Maxtena Helicore® technology, which provides pattern control, polarization purity, and high efficiency in a compact form factor. The M1621HCT-P-SMA features a screw-on design with an integrated SMA connector. The M1621HCT-EXT is an external magnet-mount antenna with a 1500mm (4’9″) LRM100 coaxial cable and integrated connector. Both antennas are rated IP67, making them well suited for harsh environments. They are ground-plane independent and offer a very low axial ratio. Maxtena M1621HCT Iridium Certified Antennas are designed for applications requiring high-quality reception, including vehicle and fleet tracking, military and security, iridium short burst data (SBD), oil and gas, law enforcement, and much more.