IC04 4 Inch IC New Construction Airtight Housing is available in a Satin Nickel finish. Must be used in any ceiling where there is insulation. This housing incorporates a box which creates an air space between the inner fixture and the insulation. Unless there is access from above via the attic, the size of the box makes insulated housings suitable only for new construction applications. Consult local codes for the requirement of a vapor barrier extender, not included. One 50 watt, 12 volt MR16 type GU10 base Halogen lamp is required but not included. 7.75 inch width x 6 inch height x 12.62 inch length.