Width is measured across the chest below the sleeves from seam to seam. Height is measured from the bottom of the shirt to the highest point on the shoulder (where the seam meets the neck).

Please note that each product has its own specific sizing chart.
SizeWidth (inches)Height (inches)
Adult Small - Green Heather17.527.5
Adult Medium - Green Heather1928
Adult Large - Green Heather21.528.5
Adult XL - Green Heather2431
Adult 2XL - Green Heather2631