This item was developed for three applications, 1) Industrial applications where managing core body temperature is paramount to worker safety and comfort. 2) To be used by theme parks and other venues to keep employees cool underneath mascot and character suits. 3) To provide relief to sufferers of Multiple Sclerosis who frequently experience heat sensitivity. Everyday uses include yard work, sporting events or anywhere combating heat is a must. Low profile vest adjust to fit most. Neoprene outer with nylon liner.