Don't let the heat get in the way of the things you love most.
It's time to take back your life, stay cool and be cool!


No one wants a bulky cooling vest weighing them down. That's why UnderCool weighs less than 2lbs— including the cooling packs!


Made from breathable mesh and wicking fabrics, the UnderCool is designed to keep you cool and dry. Our flexibility is unmatched!


Our slim design conforms to your shape, you can even wear it under your clothes. You can stay cool and no one else has to know!

"ThermApparel has flipped the script on cooling vests.
UnderCool is a game changer."

-Dave Bexfield, ActiveMSers

The UnderCool was a ”Godsend” for me during the recent Hurricane Irma.

"I live in Fort Myers FL and I was without power for 5 days and our community was flooded after the hurricane. The temperature was in the mid to high 90’s with high humidity.  Not only was I not able to leave my home because of the flooding, I had no power, therefore, no A/C and no refrigerator or freezer for those 5 days.

Because your cooling packs are made from the special phase change material, they did not require a freezer.  I have two sets of cooling packs and was able to recharge the cooling packs by placing them with the bags of ice and the frozen water bottles I prepared. I had other water-based cooling packs that were in the freezer that had all melted. I don’t know what I would have done without your PCM cooling packs!"

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