Cellar vent cover

My house is connected to domestic gas, and the gas meter stands in my cellar. One of the cellar's wall has four vertical vent holes to enable gas to evacuate should a leak occur.

The problem I had was that bugs used these holes to come inside. Spider webs, ants... you name it.

I designed these covers and equipped them with mosquito nets. Ventilation is preserved and bugs stay out. The covers are simply glued on the outside wall with neoprene.
[A short video](https://youtu.be/08DQMfFXI7s) to show how the mosquito net is glued on the backside.