I'm 6'0" and 200 lbs. This shirt suits me. XL would be too big and medium would be too small. I also bought the same long sleeve t-shirt from A4 at Revain (https://www.amazon.com/A4-Cooling-Performance-Sleeve-T-Shirt/dp/B00BPXOK84/) which is always that bit heavier Material that fits better under my arms. All in all, this Hanes is a nice shirt and I would recommend it.
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