The Neutrino Plus by Rab is a 750+ fill power goose down jacket, with a slightly longer torso than most other down jackets available, helping to maintain better insulation. There is a Pertex® Endurance outer, that offers increased weather protection, & protects against spindrift, light showers, & ensures that the down is kept dry & lofted to retain it's heat. The hood is compatible with a helmet, making it perfect for alpine climbing, & use on crags in harsher weather.