HJS

HJS Emission Technology: Over 50 Years of Exhaust Engineering Excellence

HJS Emission Technology is a German manufacturer with a singular mission: cleaner air through advanced exhaust and emission control systems. Headquartered in Menden in the Sauerland region of Germany, HJS has spent more than five decades developing and refining technologies that help vehicles meet — and exceed — ever-tightening global emission standards. From OEM supply contracts to aftermarket solutions, motorsport applications, and industrial filtration, HJS brings the same rigorous engineering philosophy to every product it makes.

At the heart of the HJS philosophy are four core values: responsibility, sustainability, quality, and longevity. These aren't just marketing words — they're embedded in the materials HJS selects, the tolerances it holds, and the breadth of coverage its catalog provides. Exhaust manifold gaskets from HJS, for example, are engineered to vehicle-specific dimensions, ensuring a leak-free seal even under the extreme heat cycles that punish lesser components. With over 1,500 references in their assembly technology range alone, HJS is one of the most comprehensive exhaust component suppliers on the market.

HJS is perhaps best known internationally for its catalytic converter and particulate filter technologies, but the brand's exhaust hardware lineup is equally impressive. Precise exhaust seal rings keep critical junction points airtight, while purpose-engineered exhaust muffler brackets and exhaust brackets provide the structural support and vibration isolation that protect the entire exhaust system from premature wear. These are the kinds of parts that rarely get attention until they fail — and HJS builds them so they don't.

For vehicles equipped with modern diesel or turbocharged engines, HJS also supplies Exhaust Gas Temperature (EGT) sensors — a critical input for engine management systems that monitor exhaust stream temperatures to protect turbos, catalytic converters, and diesel particulate filters. Accurate EGT data is essential for maintaining both performance and emissions compliance, and HJS brings the same exacting standards to its electronics as it does to its mechanical components.

HJS also holds a storied position in motorsport, recognized as Europe's leading manufacturer of motorsport catalysts. Since 1990, HJS has developed and produced catalysts and exhaust systems for competitive racing — experience that feeds directly back into the precision and durability of its street-car and commercial vehicle product lines. Whether you're maintaining a daily driver, a performance build, or a commercial fleet, HJS offers the parts and engineering heritage to do the job right.