Whether you rock an insulated jacket or layer up under a shell, the Morrison GILLTEK® from Orage is a great mid-layer option. The warmth of a micro puff insulator with out the bulk. Primaloft Thermoplume insulation in the chest and sleeves keep your core warm while stretch paneling on the back allows for breathability, unrestricted motion, and will help to prevent perspiration underneath your pack during an ascent. Toasty warm insulation and awesome breathability come together in this piece to give you an awesome mid-layer.