Flysight Black Mamba TX5820 V2 FPV VTX 5.8GHz Video Transmitter (6V-28V) 40CH 2000mW FPV Transmitter for Long-Distance Transmission 8km to 9km (TX5820 V2-RPSMA) Flysight 5.8GHz 40CH video transmitter 2000mW the most powerful FPV VTX (about 8-9km in open area) Channel button:to switch channels easily and with a high brightness LED display Special design with cover & small size,light weight,easy to carry & on-board quiet fan build-in & not affected by 2.4GHz R/C Radios Keep firmly in mind:install the antenna first before powering the transmitter,or it will be burned Antenna connector:RP-SMA (transmitter with inner pin,antenna with inner hole)