HJS is an OEM supplier of mufflers, catalytic converters, exhaust hardware and diesel processing systems. HJS has many years of experience and expertise in the field of exhaust gas after treatment. Their innovative environmental protection technologies can be used either as original equipment or for retrofitting in passenger cars, commercial vehicles, performance tuning, and a wide range of non-road applications. In addition to systems for spark ignition engines, HJS specializes in diesel engine systems as well. Whether it is for diesel particulate filters, catalytic converters or nitrogen oxide reduction systems, HJS has the right solution for almost every type of vehicle.