Lewatit® MonoPlus S 108 is a strongly acidic, gel-type cation exchange resin in the Na-form with beads of uniform size (monodisperse) based on a styrene-divinylbenzene copolymer. Due to a special manufacturing process this resin type is extremely resistant to chemical, osmotic and mechanical stress. That leads to very low leachables even under critical conditions like higher temperatures, presence of oxidants (02 , Fe-oxides) and external regeneration processes. Even at very short cycle times (one cycle = service + regeneration) the special ion exchange resin matrix leads to long life cycles in demineralization processes. The high total capacity results in high operating capacities with a very low ionic leakage and a very high regenerant utilization. The extremely high monodispersity and very low fines result in particularly low pressure losses paired with an efficient and cost optimized operation of demineralization plants.