You can buy permethrin at Dick's, comes in a 24 oz pump bottle. Not a big fan of DEET, careful with that stuff around your lines. Not only Lyme, and Rocky Mt. spotted fever as someone said, but anaplasmosis (sp?) comes from ticks also. Make sure you use preventives on your dogs, can be very painful for them. Tucking your pants in your socks will help, but they WILL get on you other ways.