You'll love the feeling of warmth and comfort of Heat Bods Invisibles Vest. Made using a specially constructed lightweight, super stretch thermal fabric that is designed to retain heat and trap warmth close to the body. Underworks Heat Bods Invisibles Vest is designed side seam free, without binding and tags and can be worn with a round neck or a v neck to ensure a smooth, invisible fit under clothing providing a perfect layer of extra warmth on the coldest days.