Rail sets include the exciting addition of rails that send your marbles zooming their way from cube to cube! The 7.5 long straight away rails attach easily to any single or double exit cube. The unique design of precision-engineered cubes allow for limitless configurations and unique building options while the rails add the traditional motion of a classic marble run. Includes: 4 marble end catchers, 10 straight-away rails, 80 cubes, 4 marble catchers and 20 marbles. Ages 6 and up.