This shirt is an outstanding quality, Oxford, Brooks Brothers button down. it is 100% cotton, but has a lot of heft and is still breathable. Not a cheap box store shirt. I love wearing this shirt over other items, even a bathing suit. Also looks great tucked in with jeans or more formally for work with a pencil skirt Only selling because it is now just too big for me for anything other than a bathing suit cover and I like to have more versatile items. 21 inches pit to pit. Most of the clothes I'm selling are 12 or 14 and I am happy to bundle.