6-12041 FT O-72 Curve Track Features: Easy, snap-together locking mechanism for sure connections Patented center half-pin allows for track orientation in either direction without the need for moving pins from one end to the next Two terminals under each piece of straight and one terminal under each piece of curved track for transformer and/or accessory power connections ? no Lockons required and Curves are O-72 to give locomotives a more realistic appearance around corners. The larger diameter also allows for the operation of larger locomotives than is possible on O-27 or O-31 track.