Expansion Packs let you expand your TrackMaster Motorized Railway by adding tracks, bridges and other accessories to any layout. Add to the adventure! The Bridge Expansion Pack features 12 pieces including bridge girders, railings and curved tracks that let you expand and connect bridges from other sets! Includes: 2 Level One Track Risers, 2 Level Two Track Risers, 2 Level Three Track Risers, 2 Level Four Bridge Stands, 2 Bridge Trusses, 1 Ascending Curved Track (Right), and 1 Ascending Curved Track (Left.