Vintage London Fog Lambskin Three quarter jacket size 40 fits as oversized M

Vintage London Fog Lambskin Three quarter jacket used but in excellent condition It says size 40 but it fits like an oversized M . This gorgeous jacket has 3 front buttons Side pockets and the lining is a 100 percent acrylic. It’s a bulky jacket feels very warm. Here are all the measurements. Length is 34.5 Pit to pit is 23.5 Sleeves are 27 Shoulder to shoulder is 19