He showed an example. Its what you pay to fly between 2 airports, regardless of connection. However domestic connections must be 4 hours or less, if over 4 you're not connecting. You're flying to that airport and stopping. Also not all airports are valid connection points. You can book AUS-ATL-LAX as one fare. AUS-JFK-LAX must be booked as separate fares, 2 RUC is thus required . (Although a lot of agents will still just use one)