These GI Expedition Weight Zip Tops are the warmest top we have.  100% Polypropylene or "Polypro" 

They are made for the military and called "Extreme Cold Weather Gear".    

They are made from 100% Polypropylene and the same material as our GI Crew Neck Tops found here.    The difference is in the collar.

These Zip Tops have a half turtle neck collar with a half zip to adjust your body temperature and ventilate when too hot.

We've been selling the crew necks for 13 years and the only complaint we get is that they are too warm.

Now you can adjust that warmth.     Made in USA

 All of our products come with a 30 day, money back guarantee if you are not satisfied.

Sizing Chart: Long Underwear: Tops:(chest size) S-34-36, M-38-40, L-42-44, XL 46-48, 2 XL 50-52