Vintage Mustard Yellow Polo Ralph Lauren V-Neck Heavy Sweater Size M

I believe this is cotton, although I couldn't find the tag listing what it is. It's in excellent used condition, without any holes or stains. Size Medium - could be unisex Armpit to armpit 23.5" Length 26" Arm Length 24" I believe it's vintage, as I could not find another one like it on line. Just a lovely sweater...