Rit Dye makes a product that you wash into your clothing. It makes the clothing have a high level of sun protection. I am going on a cruise this summer and I plan to wash my clothes with this. It works best on cotton clothes. I can't think of the name right now. I found it at Joanne's fabric store along with the Rit Dyes. It is recommended by dermatologists or so they say. I hope this helps. It would certainly be cheaper than buying the spf clothing.