The Airxcel Maxxair 10A40009K Replacement Lid for MaxxFan Roof Vents is designed to replace the lid of your MaxxFan or MaxxFan Plus roof vent (00A04301K or 00-04000K). Black-colored dome is constructed of high-density polypropylene. Constructed of high-density polypropylene | Maxxair Airxcel 10A40009K Replacement Lid for MaxxFan Roof Vent, Black