The best recovery program for hair [SEP] This product is amazing at making over-processed hair smooth again.  I have tried numerous repair and recovery treatments and this one seems to outperform them all.  The sos recovery treatment is a serum and has a fragrance similar to a serum. But you wash it out with shampoo and condition afterwards.  I routinely get compliments on the condition of my hair since I switched to using this once every 6-8 weeks.