With these large scale interlocking bricks, it's quite a rush for a little kid to see that he or she is capable of building something so big! That's just the first stage of the fun with giant cardboard blocks. Once a child connects that they can make walls and corners - they don't need any prompting. They start building grocery stores, airplanes, stadiums... there's no stopping the imagination. Dado Bricks enable little children, especially those 2 to 5 years old, the opportunity to advance in logical thinking skills, refine motor skills and explore in a big way through imaginative play! Every kid deserves the chance to see their imagination played out in large scale design. The use and reuse giant blocks get is phenomenal. Though with Dado Interlocking Cardboard Bricks- we're most elated by the scale of the play dimensions! Includes 20 Double Bricks and 10 Single Bricks. Each Dado Brick features recessed and protruding square indentations for stability. Compatible with most cardboard blocks sets. Simple assembly required. Fully safety tested.