I printed one of these for myself, cut the sleeves off. It quickly became one of my favorite shirts. There's something about the Sage color in particular that make these Gildan Softstyle shirts really soft after you wash them. 

If you like this you'll probably like our store. Check us out. We combine shipping on multiple orders. . 

Rough measurement guide: 

SMALL
underarm to underarm: 17"

underarm to bottom: 16"

MEDIUM

underarm to underarm: 19"

underarm to bottom: 17"

LARGE 

underarm to underarm: 21"

underarm to bottom: 20"

XLARGE

underarm to underarm: 24"

underarm to bottom: 20"