The Apart D-VOL30 is a 70 volt volume control. It can handle up to 30 watts of power and is very durable thanks to the step-by-step attenuation in 11 steps + zero position. The D-VOL30 is designed to handle 24 V priority signals. This means that you can always get an announcement out, even to zones where the local volume control is in the 'OFF' position. If your amplifier has a 24 V priority output, it will send a 24 V signal when you push the talk button on the microphone. The 24 V signal will close a relay on the D-VOL30 volume control, and the signal will pass, even when the volume control is in the 'OFF' position. This can be very useful for emergency or evacuation messages. The D-VOL30 is built on a universal chassis that easily can be integrated with any Decora box offering a flush mount and neat finish.