Comet Original B-10NMO 146/446 MHz Mini Dual-Band Mobile Antenna 12" NMO Connector The Comet B-10NMO is identical to the B-10, but with an NMO mount. These antennas do not include the mounts or coax. If you are going to drill a hole in your vehicle, use the NMO style mount. It is easy to install and waterproof. If you do NOT want to drill a hole, there are many more PO (also called UHF or SO239) style mounts to choose from. Very short yet efficient antenna, mainly used in metropolitan areas where extended range is not critical. Particularly used in a city or area where the repeater sites are generally higher than the mobile station due to the pattern having an uptilt.