The APK panel fan from Continental Fan was designed for applications that need high efficiency and quiet operation. This fan is available in diameters from 12 in through 36 in, with capacities ranging to 23,000 cfm. The APK panel fan has an airfoil adjustable pitch impeller for precise performance matching. Fan blades are available in either pressure cast aluminum or glass reinforced polypropylene [GRP]. Custom designs and all aluminum construction are available.