IT4000CE 3 Inch Low Voltage Non-IC Shallow Remodel Housing is designed for non insulated remodel applications. Non-IC designation requires that insulation be kept a minimum of 3 inches away from housing. Takes up to 7/8 inch ceiling thickness. Low voltage 12 volt electronic transformer included. One 20 watt, 12 volt GU5.3 MR16 bulb is required, but not included. Halogen dimmable with a low voltage electronic dimmer. See attached manufacturer dimmer compatibility reference when using LED bulb option. Suitable for damp locations. UL listed. 3.25 inch ceiling cut out. 11.1 inch length x 4.25 inch width x 3.25 inch height. A complete fixture includes a housing and trim, sold separately.