We use a vest year round. It packs smaller than a jacket and it takes care of the most essential wind blocking; protecting the chest from cold air. The one thing that bugs us about vests is that, despite all the paneling that we can find in cycling clothing, vests are usually pretty simple, and, between the cut and the typically non-stretchy windproof material, kind of baggy. This is where the Giordana Triseason Wind Vest differs most dramatically from the norm. There is extensive paneling, resulting in a closer, quieter, more aero fit.There are panels all the way around the vest. You can see that there are shoulder panels, side panels, and back panels. There is a stretchy mesh panel in the middle of the back as well as stretchy Ametista panels on the hips. All of these keep the vest close, as does the elastic at the waist, and the elastic at the armholes. The vest is made from Giordana's Sentry Light material. It's similar to their waterproof Sentry fabric, but thinner, lighter (a mere 35g per square meter), and more breathable, while remaining windproof. There's a tiny pocket in the inside back that doubles as a stuff sack. Look closely at the White version from the back and you can see it under the Giordana logo. The Giordana Triseason Wind Vest comes in Black and White. There is a rubberized pull-tab on the zipper to make opening and closing the zip easier. There are reflective strips behind the neck and along the hips. The Giordana logos are made of rubber and stitched onto the garment. Sizes run from Small to XXX-Large.