The SRD414/4 is an acoustic electronic navigational aid to enable the officer on the watch to perceive incoming sound signals inside a totally enclosed bridge in order to perform the look-out function as required according to the COLREG 1972. The device consists of one microphone sensor unit with five microphones and one master control panel with loudspeaker and optical display. The device complies with the requirements of » Directive 2014/90/EU of 23 July 2014 on marine equipment (MED).