The Lotus LED Lights Square 4 In. LED Trim is designed exclusively for insulated and dropped ceilings. It has a narrow 1 3/8” thickness that allows for versatile installation and lighting setups that are not overly dependent upon the structural layout of homes or businesses. It comes with an isolated external driver (inside an included wire box), so that you can position light and driver separately when needed. One driver for every fixture is required. No housing required.