UnderCool Unisex Sizing Guide

Size Waist
XXS 20" - 24" 51 cm - 61 cm
Extra Small 24" - 28" 61 cm - 71 cm
Small 28" - 32" 71 cm - 81 cm
Medium 34" - 38" 86 cm - 97 cm
Large 40" - 46" 102 cm - 116 cm
Extra Large 48" - 52" 121 cm - 132 cm

Waist Measurement:

Currently UnderCool comes in 6 sizes XXS - XL to fit a wide variety of body shapes and sizes, because "one size fits all" really isn't true. UnderCool needs to fit your body like a glove to give you the best cooling support.

UnderCool sizing is based on your natural waist size, not your pant size. Not sure where your natural waist is or how to get the correct sizing? 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. Then check our handy sizing guide and order the correct UnderCool for you.

Women's Sizing Guide:

Please note sizing is dependent on natural waist size, not bust, hip or pant size.

Men's Sizing Guide:

Please note sizing is dependent on natural waist size, not chest or pant size.

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.