Men's Sweat Sauna Waist Trainer Zip Vest Weight Loss Top Neoprene Body Shaper

Firstly by raising your core body temperature, so your body has to work far harder to cool down and maintain a healthy temp. This process causes the body to burn off at least 50% more fat because of the extra energy (increased energy expenditure) your body uses to cool down and maintain a healthy core temperature.

eBay