The Saikuru might look like a down jacket, but don't be fooled: its unbeatable warmth comes from synthetic Heatseeker™ Thermolite Eco insulation. That means this rugged jacket will keep you ultra-snug on those chilly spring mornings even in damp weather, and a soft neck lining ups the comfort levels even further. With WindWall™ wind protection technology thrown in, it's equally good for blustery walks when the wind chill brings the temperature down.