Easy to install in wood. Not made for metal, glass, or PVC pipe.
Fits in a 4 inch round hole.
For display cases, spice racks, insect and reptile cages, etc
These round vents are easy to install. They fit into the hole made by a drill type hole saw and are held in place by knobs on the side. They are used for ventilating soffits and eaves, insect cages, display cases and spice racks. Package of 4 vents.