Penn Plax Old Bell Aquarium Decorations REALISTICALLY BEAUTIFUL: the aquarium decoration is made out of safe, durable resin and lifelike plants. HIDEAWAYS AND PASSAGEWAYS: perfect for your fish to explore, hide in, and play in. SMALL SIZED AGED BELL: 4L x 4W x 4H CREATE A BEAUTIFUL SCENE: combine with other Penn Plax ornaments (sold separately) for a custom look.