The Rab Strata Flex is an incredibly versatile jacket insulated with the amazingly breathable & warm Polartec Alpha; this amazing synthetic insulation allows a degree of airflow to maximise breathability & comfort. The insulation is protected by Pertex Mixcrolight which works with the Alpha to allow maximum breathability & weather resistance. To further increase breathability & maximise efficiency Rab have used Polartec Power Stretch panel under arms. This four way stretch fabric provides complete freedom of movement & features Hard Face technology to improve abrasion & weather resistance. This brilliant piece is designed for fast paced & active adventures & is ideally suited for active use in cold conditions, when you are moving quickly & maximum breathability is your main priority. Polartec Alpha is a woven insulation fabric; think of it like a fluffy string vest, & is much more stable & durable than other synthetic insulation. Because of its more open weave it allows air to flow much more easily, rapidly drawing moisture away from the body creating comfortable breathable insulation for active use in in cold conditions. To maximise the performance of Alpha insulation Rab have developed a polyester mesh lining fabric that is hard wearing yet allows maximum airflow. The face fabric is Pertex Microlight, a durable, lightweight, weather resistant & very breathable 20 denier woven nylon. The combination of these brilliant fabrics & insulation results in a new breed of active warm wear that is set to revolutionise how synthetic insulation is used in the mountains. Pertex Microlight outer Mesh lining Polartec Alpha insulation (60g/m²) Polartec Power Stretch with Hardface Technology underarm & cuffs YKK full length front zip with chin guard 2 x YKK zipped handwarmer pockets Thumb loops Slim fit