Feature: 1. Use PP environmentally friendly resin material, non‑toxic and odorless, environmentally friendly materials, small pets and owners are at ease. 2. The thickened running disc is safe, stable and resistant to biting, and the thickened design of the wheel disc wall can effectively balance the rotation speed. 3. Silent black technology, no noise during acceleration, high-quality durable bearings, substantial noise reduction, and high operating accuracy. 4. Anti‑slip lines, bulge, prevent pets from falling down due to inertia. 5. To prevent gnawing, the outer edge is rounded and polished to make it more sturdy. Specification: Item Type: Hamster Running Wheel Material: PP environmental resin Color: As Pictures Shown Package List: 1 x Running Wheel 1 x Fixed Axle 1 x Nut