Rene furterer rf serum 80 is a treatment shampoo for hair that is thinning it can be use for treating reactional or seasonal thinning hair caused by stress tiredness pregnancy an imbalanced diet or new medical treatment serum 80 has a dual effect in drastically slowing down thinning hair and encouraging volume and shine for best results use rf serum 80 once or twice a week for a period of 3 months apply it strand by strand to a clean scalp and then massage it in to ensure penetration