The Metrosep C 4 - 250/2.0 is the cation column with the greatest capacity in the C 4 series with 2 mm inner diameter. It is predestined for applications which require high separating efficiency. Samples with extreme differences in concentrations can be analyzed reliably with this column. The performance capability of the column is demonstrated, for example, when analyzing sodium traces in addition to monoethanolamine (MEA). With the C 4 - 250/2.0, not only amines and transition metals but also alkaline and alkaline earth metals can be determined in a single run. With its low eluent flow, this column is particularly suitable for IC-MS coupling.