Extra ExtendedCool Cooling Packs Number of Packs:4 UltraCool is our most powerful

UltraCool is our most powerful vest

or adding a second color to your rotation

full costumes

if you typically wear a 2XL shirt or have a larger chest

wherever you need cooling most

Extra ExtendedCool Cooling Packs Number of Packs:4 UltraCool is our most powerfulRefresh your ThermApparel UnderCool 3, RallyWrap, and UltraCool cooling vests with a new set of long lasting ExtendedCool cooling packs. ExtendedCool cooling packs freeze and melt at 70F (21C) to deliver strong, comfortable cooling. Think of it like a heat exchanger: the packs pull heat out of the blood flowing through vessels near your skin, and your body circulates that cooled blood back through your entire system, bringing your core temperature