Tensage Intensive Serum 50 is the highest level of rejuvenation power of SCA Biorepair Technology. Years of research led scientists to a remarkable new technology. Tensage Intensive Serum 50 delivers the highest level of SCA Biorepair Technology, 50 Biorepair Index. Antioxidants, humectants, peptides and brightening agents have been added to provide additional protection against daily environmental damage. SCA Biorepair 50 helps with the skin's natural healing process as well as brightens the skin and is more concentrated than Tensage Intensive Serum 40. It is also a great way to boost the skin repair process when used in conjunction with Tensage Serum SCA 15 Biorepair Index.