Custom cage: What vents do you use?

[Dianne]

When I build a Melamine enclosure years ago, I used a smaller version of these....available at Home Depot, Lowes, Menards....come in a variety of sizes. Go with smaller, rather than bigger.

https://www.zoro.com/oatey-snap-in-d...SABEgJ1BvD_BwE

These plastic ones work great, as do the screw on flat variety of drain cover (further down on this same link). Speaking from experience, there is a similar vent product made of metal with fins. I would not recommend using the metal fin style as they bend with enough pressure. Luckily I had no escapees.