Large foam blocks encourage active imaginative play Helps develop gross motor skills Lightweight and easy for toddlers to move 6-piece set allows endless configurations PU foam is soft, durable, stain resistant and easy to wipe cleanThe Tumble Town Foam Blocks - Rainbow are great for tumbling, climbing and active imaginative play! The foam blocks allow kids to create their own fun adventures. The stackable 6-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 configurations, so the fun and creativity never has to stop! 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.