There are different shirts that are buy it now for each, check out photos, size is named in the wording of the one you are clicking on, I have measurements so check out measurements as they are more accurate than the size.  

The XL striped shirt has some stitching as shown in the 7 & 8 photo the outside and inside are represented just to show what it looks like, it does look pretty good barely noticeable unless you look really close.