What are t-shirts usually made of? Polyester, wool, silk, or cotton to name a few, Usually though a combination of polyester and cotton. Polyester is plastic, often recycled from used water bottles. Our tees are made from 100% cotton, becasue we prefer natural fibers whenever possible, especially next to skin. Perhaps one of the most important thing to consider, when considering a tee shirt, is comfort. Comfort is never overrated. And when it comes down to comfort, there are a couple of factors to consider: breathability, hand feel, and fit.