I took a risk with this t-shirt and it paid off!! I bought an army green t-shirt and a navy t-shirt. The reviews kind of had me second guessing my pick but I figured I could always return the shirts if they don't fit. I read the size description and chose the option that sounded like it would best fit me. X-small. A bit about myself. I'm a small guy and usually have a hard time finding fitted clothing for my body type. I'm 5'6, slim with an athletic build. Once I got these shirts I noticed it had an M on the shirt tag. I was a bit disappointed. Thought I got the wrong shirt size until I unfolded it and noticed it just might fit me perfectly. So I put one of the t-shirts on and YEEEESSSS!!! IT FITS PERFECTLY!!! They both do!! Finally a company that sells shirts for my body type. Love my new t-shirts!