I'm needing info as well. My son's baseball season starts soon. Last year, I always took a cooler with me full of ice. But then I end up soaking wet by the end of the game(s).
If anyone knows of a thin one that isn't obvious, it would be great to get some info.
Thanks!

The cooling vest did not work for me because the one I had was just too bulky. I live in Florida where it is very hot and humid. I fill a plastic container half way with water and freeze it then I fill it the rest with water and keep that with me at all times; drinking it helps bring down my body temperature a bit and I also bought one of those cooling towels which helps a lot. Hope this helps

This is what I've ordered. A little less ugly than most.
http://www.polarproducts.com/polarshop/pc/Kool-...

I wear the Polar cooling vest for three years while gardening and it works great. I have also wore it under my shirts when going out and that was not a problem. One just has to be a little "inventive" and something that works well with you. Many options out there. Good luck, wish you the best.

Thank you! You've all helped in pointing me in a good direction :)