Review on 🐭 Felix & Fido Spin Safe 15" Chinchilla and Small Animal Wheel: Heavy-Duty, Super Quiet, Ball Bearing System — No Plastic or Exposed Wood Edges, Smooth Spinning, Secure Mounting by Tasha Powell

This impeller has a major design flaw as the bearing washer pinches both the inner and outer races of the bearing causing friction in the impeller when the nut is tightened. This causes the washing machine to wear out a lot. Worse, because of this, you can't tighten the nut enough for the nylon lock to work, so it keeps loosening and the wheel falls off. This can be dangerous for a small animal. One day he pinched our chins under him. Until the stock design is considered, I wouldn't recommend this at all.