I wanted a traditional checked flannel shirt that would keep me warm in the fall. I always expect sizes to be understated. I have a 46" chest and 6'2", 220 so I have a 2XL. Size XL would fit me. Size 2XL fits me with a little sag. I can wear thermal underwear underneath. I tried it on immediately and it was sparkling. It's near 50/50 poly and cotton. After the first wash with some fabric softener it was perfect. Just a design note - it seems to have more buttons than my other flannel shirts which are closer together. This adds 20 seconds to turn on and off. Precious time elapses