Features: Removable design makes assembly easier. Non-toxic plastic steel silent bearing. Hamsters play at night and do not affect the owner's sleep. Provide a safe sport and play environment for your little pets. Ideal for hamsters, gerbils, mice and other small animals. Specifications: Color: Transparent Material: Acrylic Size: S: diameter 13CM/5.12" Notes: 1. Due to the different monitor and light effect, the actual color of the item might be slightly different from the color showed on the pictures. Thank you! 2. Please allow 1-3cm measuring deviation due to manual measurement. Included: 1 X Hamster Wheel Running Treadmill