Just got a new air condtioner for my Tenere.
The vest works pretty well. Did a test drive in 96 degree weather and was very pleased. The phase change cool packs didn't build up any condensation. It made a big difference at stops.
The packs are 58 degree and last about 3 hours. Also, freeze in only 25 minutes in ice or 45 minutes in the freezer. Although it looks a little like you are wearing a life vest. I could wear it under my jacket with no problems. The liquid is not water but a phase change liquid that is lighter than water... but only slightly. It doesn't crystalize like ice but instead is like tight packed sand. You can bash it into shape if it froze in a wierd shape.
It even comes with an insulated duffle bag to keep it in.
They fit big. A medium fits me perfectly with a 42" chest. There is a lot of adjustment capability by using the velcro straps.
Zoro tools seems to be the cheapest place to get them $107. They are $150 everywhere else. You can order them from their site if you don't like ebay.
OK, now everyone gets to call me a panzy wimp for wearing a silly looking ice vest.
This is a similar product. it uses the same packs.