SLIM DUCK Super efficient VHF antenna show a OMNI directional 3 dbd gain. They are impedance matched to a hand held radio. Utilizing the Tuned Antenna's one piece NT-MIL space age covering (strong and flexible). This flex coil matching network provides at band center low SWR as well as a + - 5 MHz from band center. Antenna tuned at 146.25 being the band center, the antenna will perform between 141-151 MHz. length 9"