ize:front height:35cm(13.7in);The rear height is 40cm(15.7in);Bottom 55*55cm(21.6*21.6in).The size is measured manually, there will be slight error, please understand. The baby learning chair is made of pp cotton, which is healthy, environmental friendly, soft and comfortable, and takes care of the baby's skin Quality: the bottom of the baby study chair has a non slip design to protect the baby's safety. The sturdy and smooth zipper is durable, light and easy to carry. It can be used in any room at home and provides a safe tool for babies to learn to sit Design: the raised back design provides better support. This is a well supported baby floor seat. You don't need pillows to help your baby sit up. It can help your baby boys and girls learn to sit and maintain sitting posture Features:360surround backrest design, ergonomic heightening and widening backrest, suitable for the baby's waist and back, effectively supporting the baby's bones and protecting the baby's bone developmen