With the cooling capacity of 9000 BTU’s, this unit is ideal up to 650 cubic feet of conditioned space. The 9000 BTU unit is built on the same base as the 12000 and 16500 units. It is designed to run off a generator that produces 2000 running watts. This unit is available in right, left, or top air discharge configurations, and is available as a “Cool Only,” “Cool/Electric Heat,” or “Cool/Reverse Cycle Heat.” We use 6″ and 4″ ducting and recommend a minimum of three 4″ round supply grills with this installation.