Standard Vent-A-Kiln pre-engineered systems are available to ventilate round or octagonal kilns. All systems have a three-year warranty and are furnished complete with: •Circular Aluminum Hood •Two-speed Fan/Blower •Overhead Counter-weight Pulley System •10 feet of Flexible Exhaust Hose and all necessary Clamps •Externally-mounted Louvered Discharge Plate If you have a square, rectangular or oval kiln, you must measure the longest dimension; that is, corner to opposite corner. Round or multi-faced kilns need only have the diameter measured. 22” Hood System utilized with 18” Outside Diameter Kiln and Smaller 1122 Complete system with 115v, 5” inlet/outlet diameter, 265 cfm blower