U-Man started developing exhaust gas recirculation coolers since 2014, up to date, we are able to offer EGR coolers for the most popular heavy duty diesel engines including Cummins, Volvo, Detroit, Navistar, etc. in the aftermarket of north America, in addition, we are also designing, developing and producing exhaust treatment system for small diesel engines (around 10HP) , which are supplied into the north American and European markets.