Clean Diesel Technologies, Inc. engages in the manufacture and distribution of heavy duty diesel and light duty vehicle emissions control systems and products to automakers, integrators, and retrofitters worldwide. The company operates in two divisions, Heavy Duty Diesel Systems and Catalyst. The Heavy Duty Diesel Systems division designs and manufactures verified exhaust emissions control solutions that are used to reduce exhaust emissions created by on-road, off-road, and stationary diesel and alternative fuel engines, including propane and natural gas. Its products include diesel oxidation catalysts, diesel particulate filters, closed crankcase ventilation systems, exhaust gas recirculation/selective catalytic reduction technologies, alternative fuel products, and exhaust accessories. This division markets its products primarily under the Purifilter, Purifier, Combifilter, Cattrap, Actifilter, Platinum Plus, and ARIS brand names. This division offers its products to original equipment manufacturers of heavy duty diesel equipment, such as mining equipment, vehicles, generator sets, and construction equipment, as well as to retrofit customers consisting of school districts, municipalities, and other fleet operators. The Catalyst division produces catalyst formulations to reduce emissions from gasoline, diesel, and natural gas combustion engines. Its products comprise catalysts for gasoline engines, diesel engines, and energy applications. This division supplies its catalysts to automotive manufacturers and heavy duty diesel engine manufacturers. Clean Diesel Technologies, Inc. sells its products through a network of distributors and dealers, as well as through direct sales. The company was founded in 1996 and is headquartered in Ventura, California.