First of all, no two size 1Xes are going to be exactly the same size/measurements. Size numbers are, at best, an indicaton, not an absolute. I've seen everything from size 14 to size 20 written up as 1X. The more expensive the item, the lower your "size" will be. A Ralph Lauren 6 might fit an Avenue size 10. That's one of the reasons women love to buy designer clothing . . . because they can quietly brag on what a small size they wear.
The best thing you can do is show the size on the label AND include complete measurements: Bust, waist, sleeve elngth, length of garment, hips, etc. That saves the prospective buyer having to write you a note and ask.
One thing that does make a difference is if the size is written as, say, 16W. That is a different cut/fit than a regular misses size 16. The W stands for womens sizing. A womens size 12 and a misses size 12 are similar but not the same. Twomen's sizes are cut differently (larger and with more ease).
