At the PD, it is trapezoid, which means 4-sided but with only 2 sides parallel. Look at the difference in length between the top side and the bottom side, designated x and y. Such a thing doesn't even exist.
No matter what you call it, they are different:
Those shapes are NOT the same, and neither one is even possible. But wait, there is a 3rd image of the dressing in which it is distinctly triangular.
So now, we have 3 shapes to the dressing: trapezoid, oblong with a bottleneck, and triangular. But, they are all fake; just trick photography. There was NO DRESSING over the sweater, which is medically ridiculous anyway. Who puts a dressing over 3 layers of clothing?