Im 5'10, 153, 37 inches at the chest and wearing a 48. m an S in J.Crew sweaters since I know lots of people here wear that and a small in MJK shirts as well to give you all an idea. Somebody in another thread was thinking about a diesel jacket or toj. I own both and they arent even close. The hardware and especially the leather are on a completely different level here. Diesels fits are pretty good but Im a skinny ass dude so this fits much better in the arms and a bit better in the body than the Diesel I have.