Not fully wind-proof, but for $50 (or less, on sale), this is great. Wore it recently on a 42-degree partly sunny day, over just a long sleeve jersey, no base layer (I generally run pretty warm) and didn't have any issue with windchill on my torso. I love the double zipper, lets me zip it up from the bottom to dump heat during a climb and then quickly re-zip for the descent, rather than single zips that flap around if you fully unzip and then you have to wrestle with putting it back together. Maybe that's just a problem for me b/c I suck at riding with no hands. Compared to any other vest at this price, it's hands-down the best. Compared to other vests in the $70-$100 range, this is as good if not better.