I'm an "off the rack" size 40 in men's jackets. According to the sizing chart in the listing, I ordered a 40 Regular. While the jacket and sleeve length are spot-on, the chest was far too tight, perhaps more like a 38.  I'm taking advantage of Amazon's excellent return policy, but I inspected the jacket and while it's not top-shelf (nor would I expect it to be) it appears to be of very good quality for the price. I normally pay much more for similar.