The gates for the fully automatic railroad grade crossings descend the minute an oncoming train reaches the contact area, and do not go back up until the last car has left the contact area. The contact area can be extended to any length desired. Any straight or curved track can be used with K Track. With C Track an existing electrical connection on the track sections must be separated. On the M Track that is no longer available only the 5115, 5116, and 5145 contact tracks can be used.