Description: The VOL850 by Rockville is a wall volume controller that works with any standard home audio or pro audio system that operates with 4-8 ohm speakers. Our volume controllers are some of the best on the market. The reliability and accuracy is what makes the difference. Our 11 step controller is precise and accurate. The VOL850 supports speakers connected to it that add up to 50 watts RMS per channel or less. For example you can connect (2) speakers that are each 50 watts. The euro-block connectors make installation easily. The terminals are fully detachable. We use a beautifully designed plate that will seamlessly match your standard decor. These are a standard 1-gang size for easy installation. Internally the circuit board is protected from dust build up to ensure long life. What is a volume controller? If you already have a multi zone amplifier then you can go out from any zone and into this volume controller and then out from the controller into the speakers (each speaker is wired from one to the next in parallel). The end result is that you can access the volume control from that room without having to change the volume from the amplifier itself.