I bought one of those cooling jackets, the ice packs are in the freezer right now , it comes with like 24 gel packs that you have to put water into, supposedly they turn into a gel when you add water to them , am going to give it a test run later today, I will look like a state highway dept worker now but I will be a cool state worker at least.
I wear an extra large life jacket , if you are any bigger that that you need to find something in a bigger size, it fits but just barely, I just pulled the whole jacket off and put it in the freezer , it does make a difference but not sure how much just yet or how long it lasts before having to refreeze the packs.