Ringtone polarized high-ohm DW type, operating under the influence of the flow of alternating current frequency 18Hz to 50Hz is used for alarm or calling. In its most basic level, is designed for use in railway wired telephone communications and announcing physical guards. The physical connectivity to one pair of wires can be attached in parallel from a few to a maximum of 10 phones AMB-1 and 10 rings all high DW.
DW bell is ringing electromechanical having two bowls lacquered aluminum with a diameter of 130 mm.
Ringtone can be installed in indoor and outdoor facilities.