Description: Non-slip convex lines enlarge friction and enhance stability to avoid false step. Your pet won't get its feet hurt or wrenched. Silent structure, your animal can run at night without disturbing others. Your pet will enjoy the happy time.It is ideal for gerbil, hamster, mouse and other small furry animals. Funny running wheel and resting place, you pet will love it. Item Name: Pet Exercise Wheel Material: Plastic Shape: Round Features: No Noise, Adjustable Height, Bumpy Track Size Details: M, Diameter: 18cm/7.09"(Approx.) L, Diameter: 23cm/9.06"(Approx.) Notes: Due to the light and screen setting difference, the item's color may be slightly different from the pictures. Please allow slight dimension difference due to different manual measurement. Package Includes: 1 x Pet Exercise Wheel