As near as we could tell the difference is the treatment of the fabric to make it weatherproof. Friend of mine had me do new Sanmar jackets 2 christmas's ago for her hubby and kids and herself-they have a couple horses and take care of a farm they are buying so it was a 'joke' to have matching jackets made up for 'manure specialists'. Her husband had a carhartt jacket that was several years old and had been washed a lot. No difference between them. New, yes the Carharts feel heavier or thicker. My commercial accounts had been using carharts and brought in the first ones until I gave him a sample of the sanmar to try. They fit better, are a little 'longer', and just at 'retail' price he saved over $30 per jacket. His rigging crew has had them for almost 2 years now and he's coming in to order all new ones-changing the name of the company and new logo. Not even a thought to go back to Carharts. Only problem we've encountered-we left a smaller black one in the front window almost a year as a sample-the black faded in the sun to washed darkish gray....can't do that again! Roland