Krinkle Collapsible Cat Tunnel with Peek Hole and Storage Bag by Weebo Pets Stimulating Sounds: Up to 52" of feline fun infused with an irresistible crinkle Tough interior metal spring and thick, double-ply outer walls with double-sewn seams Available in three sizes: 20", 36", and 52". Small dog? Medium cat? Big rabbit? Choose your fit! Hide & Peek! Peek hole in the top of the tunnel is perfect for curious cats Sets up and flattens down quick, securing with a simple knot when playtime is over