Simple block connections make it easy for little ones to stack and build-with a special birthday present block surprise! (It really opens!) Build and carry base doubles as a building surface for all-in-one on-the-go fun. All Little People® Builders sets are interchangeable. Look for more Little People Builders and build a world of fun! Bin with blocks on top approx. 9" L x 8" W x 9" H.