This is a really nice jacket, but too sleek (tight) to layer much under. Got a medium, I'm 5'9", 185#. It has a niche in my gear for milder weather, but would get a size larger for cold weather. Quality is great, and jacket looks great as well. Side pockets are interesting, as they extend all the way up the front on the inside. Maybe carry tent poles there? Great value at this price.