Outwit squirrels every time! When a squirrel steps on the base or one of the perches, his weight causes the outer caging to drop—and chew proof “leaves” cover up the ports. Once the squirrel takes off, the cage springs up and the ports are available for the birds. Springs are adjustable for various weights. Spring loaded cap keeps squirrels out. Six feeding ports. The perches are made of metal. Holds 4 pounds of seed. The tube is 3 inches wide, and the feeder is 18-1/2 inches tall.