I bought the L size first as I wear L/XL for most things and the BIG size is sometimes a bit tighter than I prefer. Spring. BIG of it is huge. Closer to XXL on every other brand I own. Significantly larger than the Calvin Klein XL jacket. Came back and got a medium. I don't have medium sized clothes because they are too small for me. However, the area is STILL too big. I'm not returning it because I'm concerned the small might be too small, so I'll be dealing with a slightly larger medium. The rest of the product is of good quality. warm, comfortable and good looking.