Fits exactly in a 12inch-wide (between sides of face frame) base cabinet. You may need a 1/4-1/3 inch thick shim in the back to further secure; any thicker and the cabinet door won't stay closed and will rest 1/8 out and not be flush with adjacent cabinets. Dry fit to select the right shim thickness. Works great. 2 compartments is great for trash-recycle.