Stem No BPA Strengthens Hand-Eye Coordination. Center Post Designed To Stack Rings in Any Order. Frustration-Free Play For Baby. Textures Rings Are Great For Mouthing. Name The Colors As Baby Stacks The Rings. Count To 8! Each Ring is Numbered For Counting. The center of each ring is the same size, allowing it to be stacked in any order for frustration-free play. Explore big & small, sorting, sequencing and building!