One piece polymeric blower wheel. White polymeric grill. Dimensions: 10 in x 10 in One - 250 watt maximum, type R40 bulb, medium base infrared lamp to deliver silent heat to the room, bulb not included. Rated type IC for ceilings insulated to R-40. Plasticcollar for 4 in duct connection comes complete with built in non-metallic back draft damper for quiet operation. UL listed. HVI2100 certified.