The DeltaBreez Green Builder Ventilation Fan marks a new achievement in ventilation for green construction. Featuring a compact housing 8.25-Feet by 8-Inch by 5.75-Inch while operating at 60-Percent less noise, and using up to 69-Percent less energy. with power consumption as low as 7.9-Watt, energy costs for operating these fans 24/7 for an entire year is as little as $8.31. Featuring DC brushless motor technology, the fans are built to run continuously for more than 70,000 hours. The DeltaBreez Green Builder is the quietest 4-Inch duct ventilation fan with this popular housing size in the market today.