Glacier Tek's Disposable Cool Vest is ideal for harsh environments and can be worn under chemical suits, Tyvek® protective suits or other personal protective equipment. A disposable vest may be used more than once unless soiled or damaged. SIZING: This adjustable-fit vest comes in one size, designed to fit up to a 52-inch chest. This is a set of 5 replacement vests only. Cooling packs are NOT included. Spare sets of cooling packs are sold separately.