Laguna's Air Filtration Unit is designed to recycle all of the air in a 20ft x 20ft x 8ft space up to 22 times per hour at its highest speed. It includes one outer washable electrostatic filter with an inner filter that captures all particles larger than 1 micron ensuring clean air output. The unit is equipped with a 1/5 HP, 60 Hz service with the option of 540, 730 or 1200 CFM.