JAXA is Japan's Aerospace Exploration Agency and like its US counterpart, it's synonymous with all things high-tech because, well, astronauts! So when it decided to collaborate on making a countermeasure for heat stroke, a real and constant danger in Japan's summer, it came up with this incredible piece of clothing: the JAXA Reikyaku Cooling Vest. Even just looking at it, you understand that this is more "sophisticated equipment" and less "cool threads" (although to be fair, it also looks cool!).
What sets the JAXA Reikyaku Cooling Vest apart from other cooling garments is that it's water-cooled: you fill the tank (carried on the belt) with 1 liter of water, fire the pump and let its network of tubes carry the cool water all over your upper body, from the waist to the neck. Its 4 AA batteries are good for 7 hours of cooling and as for its effect, your temperature will be an average of 6.7°C (44°F) lower than that of the environment. How cool (literally) is that?
The JAXA Reikyaku Cooling Vest features: