Performing as midlayer and standalone across a broad range of activities and output levelsthe iconic Atom is an Arc'teryx mainstay. Over timewe have refined the design to elevate performanceimprove durability and extend its versatility. Its Coreloft Compact insulation retains heat when wet and withstands repeated packing and unpacking. Lightsoft and durablethe Tyono 20 face fabric resists wind and weatherand stretch fleece side panels improve ventilation and freedom of movement.