Ordered the Carhartt jacket in a 4X as some reviews on Carhartt items said they ran small.  The 4X was too big everywhere so reordered a 3X and it is a much nicer fit. He is a big boy at 6'4" and usually wears 2X or 3X in t-shirts. It is still roomy enough that he can wear layers under it and it is perfect on cold days.  Did not have a problem with the return or reorder of the jacket from Amazon.