This category of two way radios includes transceivers designed for mobile use (as in fitted into a vehicle) or operated as a base station in an office or the home. Most of these two way radios operate on 12 volts DC power, so if a car battery isn't available they will need a power supply that converts AC mains power (110v or 220v) to 12 volts DC for the transceiver. The radios will also need connecting to a suitable outside antenna (either base station or mobile type). Some radios, such as military manpacks or packsets run on 24-volt batteries.