Sturdy Material: Teddy bear hamster tunnel is made of plastic prevents biting and collapsing, and the inside of the tube is smooth and burr-free, so it ' hurt your petProduct Size: Inner diameter 5.5cm. Suitable for dwarf hamster, mouse, hamster, rat,gerbil,syrian hamsterExpanding space: The gerbil external tunnel can be assembled into different shapes at , you can create mazes, hideouts or connect to other hamster habitats, creating more space for your hamster to move around, enhancing their ability to climb and explore, and fulfilling the playful nature of ratsTransparent Pipe: The transparent design of the hamster tunnel allows you to clearly observe the playful adventures of the hamster, and the breathing holes in the pipe that the hamster has sufficient air circulation without worrying about the safety of the petInstallation Note: The hamster tunnel kit is easy to disassemble and easy to clean, which can provide a clean and fresh environment for hamsters.Color:Transparent & WhiteMaterial:plasticPackage Contents:8 * Hamster Tunnel KitOnly the above package content, other products are not included.Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.