The shirt is made of a very light fabric, wearing very comfortable on the skin. Especially in the chest, it fits snug and underlines the sporty character. In the forearms it is very tight and stressed easily. It can be casual wear with another open button, which still looks elegant. Some threads on the sleeve inside, I had to cut away what I do not see as a problem.
Conclusion: Have ordered in size M shirt and wears it in with just under 171 size and very well-trained figure sporty elegant and emphasizes the sporty character without too much of a good thing.