SILENT: Silent structure for spinning, your animal can run at night without disturbing others, encourage your pet with hours of healthy exercise. Quality material: Made of high quality material, non-toxic and tasteless, can use long service life. Ideal for hamsterssmaller Syrians), Gerbils, Mice, and other similar small animals (not suggested for chewers). Perfect design: The small wheel shows translucent design, visually spacious and bright, its easy to lets you watch your pet playing inside. The edge of the cylinder is smooth that wont hurt the pets feet. Non-slip convex lines enlarge friction and enhance stability to avoid false step. Easy to clean: Whole-body washable, keep wheel clean. Package and size: The package include 1 * Wheel and 1 * Screw. Diameter: 8.3 inches(21cm). Please confirm whether it meets the size of your pet before placing an order.