When using redlights you can get them to stay longer by applying clear prizm , to all the hair, under the dryer for 20 mins, treatment is about 15 dollars extra and repeat  every  3 weeks, tell client only to use a pro/ shampoo and cond. So you have made extra 15.00, you sell your retail, and client comes back every 3 weeks for treatment. I do alot of treatments of this sort for summer as it protects the hair and adds so much shine. men and women. The redlights will stay bright