Our Crop Sleeve Tunic is redesigned from one-of-a-kind vintage button front linen shirts. This is a collarless style with a long shortsleeve. Each shirt has unique details like different buttons, some have pockets, others don't. You can see the tunics that are available, and their sizes, by selecting the different styles in the drop down Style navigation. Each measurements are slightly different. To create consistency in sizing with a loose fitting item like this one, we use the shoulder measurement to determine size.