181PSI 5.5HP 21CFM V Type. Twin Cylinder Air Compressor Pump Head Double Stage. 1181PSI 5.5HP 21CFM V Type Twin Cylinder Air Compressor Pump Head Double Stage. This item is in the category “Home & Garden\Tools & Workshop Equipment\Air Tools & Air Compressors\Air Compressors”. The seller is “yaxun_shopping23″ and is located in this country: US. This item can be shipped to United States.