Phoenix based company Incorporated in 2002 as Parnell USA, Inc Specializing in distribution and installation of EPA-certified/approved CNG / LPG conversion systems to corporate and government agencies across the United States Campbell-Parnell is committed to reducing America’s dependence on foreign oil, as well as promoting a cleaner, healthier environment, through the utilization of EPA-certified alternative fuel conversion systems. We will consistently provide the highest quality products on the market with unparalleled customer service and satisfaction. Campbell-Parnell’s primary goal is to be known as the premier provider and installer of EPA-certified alternative fuel conversion systems in the country. Our development goals call for steady expansion, with an emphasis on developing a nationwide network of trained installation and service centers.