These stretch shells are nothing short of revolutionary. The Black Diamond Highline Stretch Men's Shell is a premium alpine 3-layer shell combining BD.dry™ laminated waterproof/breathable 20,000mm waterproofness / 20,000g/m2/24hr breathability technology with Green Theme Technology’s revolutionary Breathable Water Protection, their all-new environmentally friendly PFC-free DWR with superior in performance and durability to any other DWR solution. Pair these two technologies with a fabric that’s lightweight and stretchy and you’ve to a packable stretch shell that’s the absolute ultimate in a high-output, inclement weather, shell. Fully seam taped with an adjustable climbing-helmet compatible hood, this squashes down to fit in your pack, unfurls to provide wind and weather protection in a jacket with a full range of movement and pit zips, should you need to vent some additional steam. A great piece for anyone who likes to get outside and move during the winter, and stay dry in the summer, with space for layering without being bulky with extra fabric flapping when you don’t. It’s the stretchy, durable, waterproof breathable we’ve been waiting for.