Double Lens Spacer Foam & Double Lens block moisture & eliminate fogging while allowing for optimal breathability. Air Control System (ACS) ACS ventilation incorporates lens air intake vents on the goggle lens & frame air outtake vents on the bottom of the goggle resulting in a sophisticated ventilation system against condensation & fogging. Antifog on inner lens Enduro double lenses include a soft inner lens which features a stronger built-in antifog solution than any other SCOTT lens. When riding Enduro races fog should never be an obstacle.