Focused versatility. Functional minimalism. So compact and light, there is no reason to leave it behind. The Atom SL is for situations when insulation is required, but in an amount that meets milder conditions. The soft Tyono 20 outer balances airflow with wind protection and has DWR finish for protection from light showers. Placed at the chest and back, the Coreloft insulation is efficient, light, and compressible. Stretch fleece side panels ventilate and an uninsulated hood adds coverage.