Compared to the factory oiled felt drag washers, greased* carbon washers deliver up to 20% max drag increase with a much smoother drag across the full drag range. Offer zero start-up inertia regardless of how much you try and button down on the drag.  Increased durability and lessened sensitivity to moisture. They also help eliminate line jerk (the tendency of a drag to need a bit more pressure before it starts giving out line).