Large foam blocks encourage active imaginative play Interactive square block is reversible and plays music or sounds when touched Helps develop gross motor skills Lightweight and easy for toddlers to move 5-piece set allows endless configurations PU foam is soft, durable, stain resistant and easy to wipe cleanThe Tumble Town Interactive Blocks with Sounds are great for tumbling, climbing and active imaginative play! The square block is reversible and plays different music and sounds on each side. The music notes play 6 different songs on one side while the crash pad plays 7 fun action sounds on the other. The stackable 5-piece set is made of a soft PU foam which is comfortable, durable, dense, stain resistant and easily wiped clean. The material is CertiPUR-US certified foam and does not include any additional phthalates. The blocks can be stacked in endless, creative configurations, or knocked down to hear the fun sounds! Building with the blocks also help kids develop gross motor skills. They are also lightweight which makes it easy for toddlers to carry. Recommended for kids 9 mos. - 3 years.