DESC: PetBlvd.com offers: Silent Spinner, Regular is the wonderful, whisper quiet workout wheel for hamsters, mice, and gerbils. Patented ball bearing technology makes these wheels super silent. Silent Spinners work two ways free standing or attach directly to any wire cage. High quality plastic funning surface is safe and comfortable for your furry friend's feet. Available in blue, purple, red, and green. 6.5" diameter