SHIRT MEASUREMENTS: (measurements are approximate) SMALL: COLLAR TO SEAM: 23 inch / 58.4 cm ARMPIT TO ARMPIT: 16.5 inch / 41.9 cm MEDIUM: COLLAR TO SEAM: 24 inch / 61 cm ARMPIT TO ARMPIT: 18.75 inch / 47.6 cm LARGE: COLLAR TO SEAM: 24.5 inch / 62.2 cm ARMPIT TO ARMPIT: 21.25 inch / 54 cm XL: COLLAR TO SEAM: 25 inch / 64.8 cm ARMPIT TO ARMPIT: 22 inch / 55.9 cm 2XL: COLLAR TO SEAM: 26.5 inch / 67.3 cm ARMPIT TO ARMPIT: 25 inch / 63.5 cm