Miyachu Quiet Ventilation Soundproofing Noise Reduction Ventilation Grille

Silent Ventilation TSS-100SK
Size: Outer Diameter: φ86mm Depth: 70mm
List Price: 10450

I purchased these for noise reduction, but they didn't quite fit, so I'm selling them.
This is a set of two. For one of them, I've already attached the sponge and inserted it into the ventilation opening once for testing.
The other one has not had the sponge attached and is brand new and unused.

Thank you for your understanding of used items.