This is a very nice vest.  My husband weighs 140 and is 5 ft 8 inches, chest is 36.  The medium was way too big we had to pull the back belt all the way for a good fit in the front, the small just fits.  He usually wears a small in everything, with room to spare.  The color royal blue is just what we wanted.  We returned the medium, the $$ was promptly refunded.