$199.99 USD

This product is currently unavailable.

Find long term relief with 1 signature UnderCool vest and 1 set of cooling packs!


This Purchase Includes:

  • 1 UnderCool vest in your choice of color, white or black
  • 1 set of cooling packs(SlimCool or new ExtendedCool)

UnderCool features:

  • Adjustable straps and a velcro front for the best fit and comfort
  • Wicking fabrics and built-in mesh panels to keep you dry and comfortable
  • Cooling pack pockets along back
  • Cooling relief for up to 1 - 3 hours* depending on cooling pack
  • 30-day money back guaranteed

Please review our sizing chart below to ensure the best fit for your UnderCool:

Size Waist
XXS Women 18" -  22”

Women 45 cm - 55 cm

Extra Small Women 24" - 28"

Women 61 cm - 71 cm


Women 28" - 32"

Women 71 cm - 81 cm

Women 34" - 38"

Women 86 cm - 97 cm

Women 40" - 46"

Women 102 cm - 116 cm
Extra Large

Women 48" - 52"

Women 121 cm - 132 cm
XXL Women 54" + Women 137 cm +

Waist Measurement:

If you bend to the side, you will crease in the middle of your body; this is your natural waist. That's where you want to take your waist measurement.

Womens Sizing Guide:

Please note sizing is dependent on waist size not bust size.

ThermApparel recommends ordering a size smaller than your usual T-shirt size.
(If you wear a large T-shirt, a medium UnderCool will fit best.)

Other Resources:

Please review our Return and Exchange Policy here and our Warranty Policy here.


Consult your doctor or health care professional prior to using this or any cooling products for a medical condition. ThermApparel LLC will not be liable for injuries or damages resulting from the misuse or misapplication of our products.

*Cooling times may vary depending on your level of activity and ambient temperature. 

Please Note:

  • All prices listed in USD
  • International orders: your country’s taxes and duties are NOT included in the price or shipping

Questions about our vests or shipping? Reach out to the ThermApparel team toll-free at 855-232-7233, write to us through our website’s contact form or chat with us via live chat. We always respond because, otherwise, that wouldn't be cool.