|For an all around cold weather jacket the Core4element Summit Jacket is tough to beat. It sets a whole new standard for lightweight synthetic jackets. Core4elemexnt uses the highest grade, most efficient, Primaloft One insulation. Primaloft One is 92% efficient dry and 90% efficient wet making it the highest performing insulation in the wettest of weather. The Summit Jacket is extremely compressible so finding a place for it your pack is easy. Primaloft One is highly breathable, highly water resistant and very compressible. To make it more efficient, Core4element body map it with 90 gram Primaloft One insulation on the shoulders and the core of the jacket and with 60 gram Primaloft One insulation under the arms and the center of the back. From the high alpine basins to the cold nights in the desert the Core4element Summit Jacket will keep you warm.