Dispose of the vest, not your safety. The Disposable Cool Vest is ideal for harsh environments and can be worn under chemical suits, Tyvek® protective suits or other personal protective equipment. Made just for the Disposable Vest, the tri-pack GlacierPack set that is included is manufactured using 100% biodegradable materials and contains no hazardous materials. This is important for the planet as well as for workers in hot zones, hospitals or any environment where excessive heat can lead to further disease. SIZING: This adjustable-fit vest comes in one size, designed to fit up to a 52-inch chest. Set includes 1 set of packs & 5 vests