One of the lightest synthetic insulated jackets on the market, the Ultralight Aero Insulator uses space-age Primaloft® Gold Insulation with Cross Core™ insulation and our lightweight 100% recycled 10D nylon fabric for an impressive warmth-to-weight ratio without sacrificing features or durability. Removing the exterior quilted channels increases loft and traps warm air, providing thermal protection when you need it most. This is our go-to insulator style for light and fast missions.