Bug repellent /sun screen
It usually takes me about 5 minutes outside before I'm burned to a crisp by the sun and eaten alive by bugs.  I'm hypersensitive to bug bites and tend to swell up quite a bit, so when I had to attend a birthday party in July in a state park in Florida, I went out and bought this.  I didn't have one single bug bite!  Nor did I get a sunburn.
Rating: 5 stars