Not all SCR Systems are the same... Do you understand the differences and how SCR Technology Works? SCR uses DEF to reduce the harmful NOx Gases and actually converts them into Nitrogen Gas and H2O (Water Vapor). By injecting DEF this transformation happens. NOx Gases are only created at High Exhaust Temperatures so there are less NOx Gases when idling and low RPM usage of the Tractor. BUT Not all SCR Systems work the same. Some use a Pre-Programmed Dosing Rates and Inject DEF if it needs DEF or Not. What AGCO does is measured the NOx Gases after the Turbocharger with the Pre-TreatMent NOx Sensor then based on reduction of NOx Gases Required inject DEF with Dosing Module and then reads the NOx Gas level after Treatment and varies the rate of injection based on the requirements mandated. If no reduction required no DEF is used. AGCO system is different and the rate of dosing is less than competition...saving you costs and allowing to get more done on less costs.