To find your perfect Unisex size, grab your favorite tee shirt, lay it flat on a table, take a few measurements, and pick the closest matching shirt. If you are in between 2 sizes always go on the larger, chances are your favorite tee has shrunk a little since you got it. For a looser fit, order your standard size or size down for a semi-fitted look. Material: Most t-shirt colors are 52% cotton, 48% polyester, Athletic Heather & Black are 90% cotton,10% polyester, Lilac are 100% cotton