Has anyone used an Antminer Airflow Noise Reducer?   Any feedback on the amount of noise it helps to reduce?

https://www.ebay.com/itm/Antminer-Airflow-Noise-Reducer-4x12-Silencer-D3-L3-S9-APW3-Bitcoin-Miner-NEW/122751350608?epid=1767811696&hash=item1c948cf750:g:n3UAAOSwX3FZ-xVx