HJS Emission Technology GmbH & Co. KG is a medium-sized company founded in 1976 and based in Menden in central Germany. HJS has many years of experience and expertise in the field of exhaust-gas aftertreatment. More than 450 employees are engaged in the development, production and marketing of modular systems for reducing pollutant emissions. These innovative environmental protection technologies can be used either as original equipment or for retrofitting in passenger cars, commercial vehicles as well as in a wide range of non-road mobile machinery and stationary applications. In addition to systems for spark-ignition engines, HJS also offers solutions for diesel and gas-powered engines – especially solutions for reducing the emissions of soot particles (particulate matter, PM) and nitrogen oxides (NOx). With its extensive portfolio of patents for DPF (diesel particulate filter) and SCRT (Selective Catalytic Reduction Technology) systems, and cooperation with Germany's TÜV certification agency as well, HJS sets benchmarks internationally.