All measurements are in inches and are approximate.

S M L XL XXL
Chest 20 22 24 26 27.5
Shoulder 19 20.5 22 23.5 25.5
Sleeve 33 35 37 38.5 39
Length 25 26 27 28.5 29

Chest - Measure across from pit to pit.
Shoulder - Measure across from the highest points of the shoulder seams.
Sleeve - Measure from the centre of the collar to the end of the cuff.
Length - Measure from the base of collar to the bottom of the hem.