Size Width Length
Extra Small 20" 27"
Small 21" 27.5"
Medium 22" 28"
Large 23" 28.5"
XL 24" 29"
2XL 25" 29.5"
3XL 26" 30"
Width
Measured from 1" below the armpit.

Length
Measured from the middle of the collar seam down to the bottom edge of the jacket.