Review on 🔇 Quiet PC Cooling: HONBAY 40PCS Black Rubber Anti-Vibration Screws for Noise Reduction in PC and CPU Case Fans by Franklin Richardson

Works exactly as I expected. They are soft enough to easily thread through the appropriate mounting holes on the fan and case, but strong enough to hold the fan in place and isolate it from the case to prevent noise. An added bonus: They're soft enough to be used in places they weren't originally intended for (like attaching a 120mm fan to a finned CPU rack when I lost the original mounting zip ties).