IT2000CE 4 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. Below ceiling accessible. Takes from 1/2 to 1.25 inch ceiling thickness. Low voltage 12 volt electronic transformer included. One 42 watt, 12 volt GU5.3 MR16 bulb is required, but not included. 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 5/8 inch ceiling cut out. 13.6 inch length x 5 inch width x 3.75 inch height. A complete fixture includes a housing and trim, sold separately.