The original Colombian thermal shorts (Ultra Sweat). Made from 100% neoprene rubber, which is a type of rubber. The shorts have no zippers, metals, or hard materials. Works to dissolve fat up to three times more. Wear for two to three hours a day, preferably during workouts or walking. Available sizes: Small Medium Large Its sizes are larger than the regular size. Colombian made. Outer color turquoise and inner color black.