The Material is a very Expensive feel. Super long yet Elegant. It’s best to wear with heels or wedges of some kind. Each size Runs a little big, but it fits beautifully. It also comes with a belt. Throw in the dryer with a fabric softener for only 1 minute to get wrinkles out. The XL fits sizes 16-20 . If you wear a Small you can also wear a Medium.  If you normally can wear a Large you can also fit a Medium. I was wearing a Medium and it ran a little big. I am 139 pounds .. 5’5