Inspired by ski mountaineering history, this is our original model that started it all! Now in three different versions. The right pair for you depends on your main activity. Heron Glacier 2.0 has a darker, category 4 lens for prolonged exposure to strong sunlight. Heron Mountain 2.0 is more versatile with a lighter, category 3 lens. While Heron Ocean is our polarized version ideal for sea activities.