Introducing Catty Stacks Zebra and Giraffe animal prints, available June 21, 2014! Cat furniture has never been this much fun. We all know cats go nuts for cardboard boxes, so we thought “Why fight it?” and set out to build the most durable, attractive, easiest to assemble cat boxes you can buy. These eco-friendly, modular cat cubes are made from incredibly strong Corrugated Ultraboard™which is recycled, recyclable, and colored with vegetable-based ink. Catty Stacks secure to each other forming stable climbing structures and can be easily moved and rearranged, helping maintain your cat's interest while promoting healthy exercise. Cats love playing and napping inside and on top of Catty Stacks. Suitable for multiple pets up to 20 pounds each.