Summer is hot. Especially if you are being active outdoors. So to avoid getting overheated, I made a simple thermoelectric cooling unit that attaches to your wrist. This is able to rapidly cool your entire body.
You can use this to cool down after a workout or between plays. The unit is small and easily portable. All you need is access to electricity such as a 12 volt battery.
Here is a video walkthrough of the project.