Penn Plax Cat Toy Activity Center with Sisal Ball, Bells and Swatting Balls, 11 Inches High 1. Putting the fun into functionality, the Penn Plax Cat Carousel Center satisfies a bunch of kitty cravings in a single compact tower that offers plenty of variety. 2. The scratching ball is made of tough, sturdy sisal. Strategically located in the center of the cat toy to create a little extra challenge for your pet. 3. Plush lounge area on top for cats to climb up and sleep on. They will love this perch to play around on or keep a lookout. 4. Keep your cat fit! Plush hanging swatting cat toys encourage plenty of activity and stimulating swatting, enough for multiple cats. 5. While this cat tower is darn cute, good looks are only part of it. Sturdy construction and durable materials will take everything your cat can dish out, for long-lasting enjoyment.