Because of the heatwave in Southern China, air-conditioned vests have become very popular and over four thousand have been sold in the last three months, according to a report in China Daily. The vest keeps the wearer cool by circulating cold air through small tubes fitted into the vest.
Credited with the design of this particular vest is Wang Yan, a businessman from Nantong in the Jiangsu province.
The vest is made of impermeable fabric that keeps cold air from escaping. Compressed air is pumped through a vortex tube inside the vest and the vortex tube produces a cool airflow within the vest. The vest can lower the temperature around the wearer by up to twenty degrees Celsius.
The temperature can be regulated through two valves on each side of the vortex tube. One valve controls the flow of compressed air, while the other valve controls the output of cool air.
Yan has apparently sold out his vests, which sells for about 200 yuan or 33 USD.