The EVA sauna suit is made from EVA nylon and is more comfortable and effective than cheaply constructed vinyl suits. The EVA sauna suit keeps body heat in, keeping muscles warm and enabling you to burn more calories and shed water weight. This is a great tool to use for cardiovascular workouts and aerobic conditioning. The Mdeium / Large size will fir approximately a 24 - 40" waist. The next size up, Large / X-Large will fit 24 - 44" waist and the largest size, th X-Large / XX-Large will fit 26 - 50" waist.