Yeah. The golfers are right... I've been a wetland biologist for more than 20 years, never once sprayed DEET on my skin. Even in nasty swamps, just spraying my hat is usually all that's required. And concentration over 50% is worthless.The level of DEET (10%, 30% or 100%) refers only to how long it remains effective. If you’re going to be outside for 10 hours, use 100%. For two hours, 25% is adequate. DEET reacts with chemicals released by your body to confuse and deter mosquitoes. It has no effect on clothing. That’s a complete waste of money. I see it all the time especially on golf courses. People spraying their hats!