Four themed blocks for baby with an extra fun surprise—rollerballs with pictures that spin around inside! Each square Roller Block has a round rollerball inside that adds a fun new "spin" to traditional block play. Roller Blocks are super easy for baby to stack since they fit one atop another, and they roll, too! As baby rolls them along, the pictures spin inside! Great for play as a set—and even more fun when you bring them to your Fisher-Price Roller Blocks Play Wall. (Roller Blocks Play Wall sold separately and subject to availability.)