This is a fun interactive toy. This toy includes 2 round acrylic pieces approximately 2 3/4 inches in diameter and a roll of cash register paper for your bird to shred and is also refillable. This product mounts on the inside or outside of any cage. Warning! Thermal paper has been known to be harmful to birds if ingested. We use a non-thermal bird friendly paper product such as "cash register paper". 3" Long x 2.75"