Full-loaded activity center to keep birds active. Place it on top of the cage to give birds a change of scenery. Features rope perches, ladders, swings, bells and toys. Choose from several sizes (based on availability). Playpens have more perches and ladders as they get bigger. Configuration of equipment varies by each model. Sizes and bird recommendations: Small measures 9L x 9W x 9H inches Small is ideal for Parakeets and other small birds Medium measures 9L x 11W x 10H inches Medium is ideal for Parakeets and other small birds Large measures 10L x 14W x 10H inches Large is ideal for Parakeets and CockatielsExtra large measures 19L x 15W x 12H inches Extra large is ideal for Cockatiels and small parrots About Penn Plax: Penn-Plax is a family-owned company in operation since 1959. They specialize in creating excellent pet supplies for animals both great and small. Best known for producing pet products at affordable prices, the Penn-Plax brand is synonymous with innovation and quality, keeping your pet foremost in mind. Size: Extra Large.