What I mostly need is the pit-to-pit measurement. I'm trying to get a feel for which size I'd be. With a button down over a T-shirt, I've got a resting chest of 43.5 (45.5 expanded). I'm in an email conversation with Holly, but I'm trying to come into these exchanges with as much info as I can, to facilitate things and make it easier on her end. I can't seem to find these figures anywhere. Thanks guys.