Description The tunnel external plug of this hamster cage is made of high-quality plastic, which is strong and durable. Its small hole design can better ventilate the tunnel, and you can use it indoors or outdoors. And suitable for hamsters, squirrels, hedgehogs, guinea pigs and other small pets. Features - Color: Random color.- Material: Plastic.- Size: 5.50X5.50X5.50cm/2.16X2.16X2.16inch.- Creative tunnel toy accessories, plastic material, superior quality, sturdy, not easy to be knocked away by naughty hamsters.- It can be used outside the cage. The small hole design of the interface plug can better prevent the baby hamster from hypoxia in the tunnel.- Expand your habitat and provide more space for pets. There are many colors to choose from.- The hamster tunnel accessory is a safe place for curious creatures who wish to explore and promote exercise and develop healthy habits.- It can be used outdoors, which can better protect your hamster from running out of the tunnel to run away.Packing list: 4 x cage external plugs