3 different channels, one with an easy open gate, can be positioned in a straight line or at right angles. All 3 blocks can easily slot onto each other, and included are 3 interlocking stacking blocks so the children can have different heights. These canals are timber, strong and robust and a decent size to make and impact. Includes (1) 4' long channel, (2) 2' channels. Indoor or Outdoor use.