Microphone input expander box for either 12 or 24 volt operation (voltage to be specified on order details). Allows an existing P.A amplifier with one microphone input, to accept 2 microphone inputs, input 1 for drivers microphone (with priority) and 2 a courier microphone. Item can be for 4 pin Bosch or 5 pin Actia systems, please specify on order. ** Please contact to check availability before ordering