I cost less than $5, go over your head, can be used both on and off the bike, and can save you from going completely insane whilst bicycle touring in Western Australia.
If you plan on bicycle touring in Western Australia, I would recommend one of these as the flies can get quite bad. They tend to fly up your nose, in your eyes and ears, land on areas of sweat on your face, and tend to drive you crazy.
I wear one when riding when the flies get really bad at certain times of the year. I place my sunglasses on first, then I wear a cyclist’s peaked cap with a UV rear flap to protect my neck, and then I put the fly net on.
I then put my helmet on over the top of all this. The sun visor of the peaked cap tends to keep the net far enough away from my face, so the flies can’t get me.
To be able to drink whilst riding, I use a water back pack, commonly called a hydropack, and I poke the drinking tube up the inside of the fly net where it pulls tight around my neck area. This allows me to be able to drink without having to stop and take the fly net off.
Taking one of these on tour is guaranteed to protect your sanity both off and on the bicycle.
