Ash-free combination of additives for the prevention of malfunctions in the SCR system of diesel engines. Reduces the formation of deposits in the AdBlue® tank and AdBlue® injection system. Guarantees extremely fine atomization of the urea solution by lowering the surface tension. Optimizes the return flow of the AdBlue® into the system, thereby minimizing the risk of AdBlue® crystallization. For all SCR systems that are operated with 32.5 % urea solution (AdBlue®, DEF). When adding to the AdBlue® tank, should ideally be added after the filling process.