The 509 FZN LVL 1 Pant is our lightest weight and fastest drying base layer designed for high-energy riding in harsh conditions. The key to staying outside all day is staying dry, and that’s why this base layer pant goes beyond grandpa’s long johns to quickly wick away sweat. It’s part of 509’s Active Layering System™ featuring Cold Armor™ technology that, when paired with 509 outerwear, creates the ultimate defense against the elements.