As I mentioned in my hiking post, we tried out these mosquito bracelets and they worked great. Neither the little monkey nor I got bitten. And it is all natural. It does't smell bad, but the smell is strong. Supposed to last 250 hours and is reusable. We use it and put it back in the zip lock package. As we use it, I can give a better idea of how long it lasts. But I find it best around the ankle. I had it around my wrist and every time I raised the camera toward my face, the smell was really strong. So after a couple of times, I switched it to the ankle. Works great so far. We bought ours from Amazon.