I'm 5'11" about 200 lbs and the X-Large fits great. Have put off spending the money and put up with the occasional slag burn. I weld/cut as a hobby and for repairs so it's not often. Have been welding/cutting a bit more lately, arms were looking rough at a family gathering so decided to spend the dollars. Glad I did and should have done it long ago. Well worth the money, will last many years and was silly to not get one sooner. Cut a couple bumper bolts a couple days ago (on my back, on the ground, under the car a bit), wore this for protection. Was amazed at how many black spots it had on it - that would have been burn marks. Nothing burned thru the jacket - highly recommend.