The Waterproof Anorak from On packs in practical features to keep the weather out. Like the elasticated tie to pull the hood tight or keep it out of the way. Then there’s the hidden vents for increased airflow. And when the rain stops, the anorak packs into its own inner pocket for easy portability. The jacket also has a three-layer membrane which allows the jacket to be completely water and wind-proof. Dynamic breathability means that the more you sweat, the more breathable the jacket becomes due to the hydrophilic elements in the lining.