The COPPUS DDHH (Double-Duty Heat Killer™) is a powerful industrial fan designed for cooling products, processes & personnel. With airflows up to 17,000 cfm (28,890 m3/hr) the DDHK is the most powerful and versatile portable air movers on the market today. The patented, adjustable guide vane design allows air flow control – from a gentle breeze for personnel cooling, to a concentrated jet blast for product and process cooling.