I tried on a 40L and 42L, I and found both were a bit long in the body but need the long in order to have sleeves long enough for me. As a point of reference, I am 6'2" and 180 with a 42" to 43" chest. Long arms but short torso (high waisted). The 40L was very close but binding a bit in the shoulders. Several of the G&B staff looked at both sizes and advised a 42L over the 40L, although I was within a hair of going with the 40L.