These wheels replaced the stock wheels on the Dowinx LS-6689. Good: These wheels are much quieter than the original wheels they replaced. Chair (just a few cm) - These single wheels are easier to roll than double wheels - They are stronger than the plastic wheels they replaced - They look better than the wheels they replaced good for rolling back and forth in a straight line (perfectly smooth if you're going in a circular path) Conclusion: for the price these are really good wheels, not perfect but definitely worth it if your chair has noisy or ugly plastic wheels.