3 years & up. Build to new heights with this fantastic collection of realistic pretend bricks, blocks, and rocks! This set of lightweight foam builders stack easily for endless creative building projects. The foam construction is water proof, but not UV-resistant; if kept outside for a long time, the colors will fade. Included: 20-piece Cinder Block Set, 25-piece Rock Wall Builder Set, 25-piece Brick Builder Set, and 25-piece Ice Brick Builder Set. Activity cards included.