This is our lightest mid layer. Weighing virtually nothing, with an ultra-streamlined and minimalistic design, you won't notice that you're carrying it. You will, however, notice that you're wearing it; it's protective enough to keep you warm and high-performance enough to keep you dry and comfortable during fast and frenetic activity. Designed with flatlock seams - and no shoulder seams at all - to further reduce bulk and boost comfort levels.