The ISA-253 is a 16 watt in-wall amplifier/mixer that mounts into a standard 3-gang deep masonary box, such as the RACO 697, the BOWERS 3-MB, or equivalent. Each of the amplifiers’ two inputs are selectable between a balanced Lo-Z microphone level or a balanced line compact size level input. Both inputs have a seperate volume control. Their in-wall chassis’ are made of a rugged .063” aluminum coated with an off-white epoxy based paint, and the faceplate consists of a tough polycarbonate overlay. It also features a removable locking door that is available easy operation with either a keyed camlock (standard) or a thumblatch camlock (optional). The ISA-253 is powered by a UL listed 40VA wall transformer that comes with the amplifier. The amplifier proselectable inputs vides selectable 20VDC phantom power for each of the microphone inputs.