Permethrin is no joke. It is standard issue for anyone in the army that is deploying to a "tick infested" area. It is sprayed on to your clothes (DO NOT PUT IT ON YOU!!!) and will stay in them for several months and roughly about 20 cycles through the wash. Also, it does not kill ticks as much as it repels them. Keep in mind that it is easily smelled by deer, coyotes and the like. It is not really meant for hunters trying to be un-noticed in the woods, but for people that are outdoors to stay tick free. I used to give the briefs to all deploying soldiers about anything medical and Permethrin was one of the main topics. As an avid hunter in Louisana and Texas where ticks are very common I do not use it. It is one more way for my quarry to evade me. I just check for the little buggers when I get back home. Good luck.