Licence Free UHF/FM Radio with up to 8Km range, Combine 16 channels. 121 privacy codes, and 1963 Pri Combinations and communicates with all other 446 Radios. Provides up to 5 easily recognisable call alerts for incoming calls A unique circuit extends the life of your batteries. If there are no transmissions within 10 seconds the until will automatically switch to battery saver mode Roger Beep Confirmation tone indicates the completion of the user's transmission, and signals to others it is clear to talk. This feature is selectable and can be turned on or off