DR Secret T Series mean Treatment Series. The new treatment version was introduced in 2007. There was three items that was replaced: #2 Toner - T2 Toner #3 Skinlight - T3 Skinlight #4 Skinrecon - T4 Skinrecon The old version has been phrased out and it is not in production. What is the new DR's Secret T Series about? It means it is a treatment series to enhance skin …