PL259 Plug commonly used for the connection of VHF antenna's to radio's and antenna splitters.used up to a maximum frequency of 300MHz, in Amateur (HAM) radio, Citizen band radio (CB) and Marine VHF radio applications.
This connector is 50ohm impedance. VHF and AIS systems all use 50ohm connectors and cables. For good system performance it is important to use the correct impedance cables and connectors otherwise losses will occur in your system.