The PDP (propeller) High Efficiency II gas-fired unit heaters are a generation of products that are inexpensive to install, easy to use, and offer excellent in-service economy. MODINE Vertical Gas Fired Propeller Unit Heater, Power Vented, 175000/140000 Btu/hr, 115 VAC, 4.55 A, 2550 cfm, Natural Gas, 1/2 in Gas Connection, 51 deg F, 17 ft Mounting Height, Steel, Aluminized, 23-1/2 in W x 29-9/16 in D x 35-1/4 in H, Domestic