Features: This quiet hamster exercise wheel features a stable nonslip base and quiet rotation system, allowing energetical small pet to run safely without disturbing household peace. Use selected plastic with ventilation design while maintaining safe for pet interaction. Great for pet owners searching engaging fitness solution for dwarf hamsters, gerbils, or mice needing daily physical activity in cage habitats. Perfect for place in rodents cages or playpens, supporting night exercise routines when small pet most active yet owners require undisturbed sleep. The running wheel prevents slippage while the easy to install design simplifies cage cleaning, great enrichment tool for promoting natural rodents behaviors through safe, stimulating movement. Specifications: Component: Plastic Product Size: Approx. 12cm/4.72inch Color Option: 01/02/03 Package Includes: 1PC Hamster Exercise Roller Ball Toy note: Please allow 1-2cm errors due to manual measurement. Due to the differences between different monitors, the picture may not reflect the actual color the item.