Unsure of your size? Take one of your own (non-stretch) shirts that fits well; measure it from the bottom of one armpit across to the other armpit and double the result. Compare the measurement with the "Actual armpit seam to armpit seam (inch/cm)" box displayed below. If it falls between two sizes, we suggest you order the larger size.

For example, measurement = 24 inches; X 2 = 48 inches; the right size is M.

Sizes Actual armpit seam to armpit seam (inch/cm) Fits chest (inch/cm)
S 46" (117 cm) 36 - 40" (92 - 102 cm)
M 48" (122 cm) 38 - 42" (97 - 107 cm)
L 50" (127) 40 - 44" (102 - 112 cm)
XL 52" (132 cm) 42 - 46" (107 - 117 cm)
XXL 54" (137 cm) 44 - 48" (112 - 122 cm)