Cotton material. 100% cotton. There are some areas under the armpits that have become whitish, possibly due to rubbing. Please see the second photo. Spare buttons are included. Please see the third photo. Although it's size M, it has a roomy fit, like an L. The sleeves are rounded and have buttons. Since this is a personal inspection, I'm looking for someone who doesn't mind minor details and can understand. Please take a good look at the photos before considering a purchase. Instant purchase is OK, but please refrain from price negotiations (^-^) Thank you very much! #Navy #Cotton #100%Cotton