Human beings are incredible evaporative cooling systems, but that doesn't mean you can't use a little help when things are really hot. These cooling bandanas work wonders.
During a recent heatwave, my daughter and I had to cross the Nevada desert in an AC-less VW Van. This was done to honor my parents 50 years of marriage. Our family shows love with great suffering. The kid and I relied on these Miracool bandanas to help us survive.
Sewn into the lining are absorbent gel crystals of some composition. When soaked in h2o they really expand. Slowly the gel releases water, and its evaporation cools you down.
We found they'd last a full day, but needed to be resoaked after a full day of driving in such a dry climate. Soak them overnight in the fridge for an extra cold start to the day.
You get a pack of 4 for $9.