Review on Ycozy Cat Doors: 4-Way Rotary Lock Cat Flap Indoor Pet Door for Cats, Kittens, Small Dogs - Easy Install on Doors, Windows, Cupboards, and Walls - Non-Metal Safety Gate for Pets by Olga Allen

I installed this in a solid wood exterior door (one of the doors with inset panels). Cutting the hole was easier than expected (using a drill press and a jigsaw) and the overall installation was fairly easy. The instructions say that "Wood Skin" should ideally be used to seal the cut portions of the wooden door. I've never heard of it and googling doesn't help much. I'm assuming it's some kind of duct tape. Instead, paint or varnish can be used to seal. I didn't either because I'll be replacing that door in a few years anyway. Two small notes. First of all, the button for setting the lock (entry/exit, only entry, only exit, closed) is only marked with a small arrow. There is no way to tell how the door is installed just by looking at it. Secondly, there is a notch on the bottom of the plastic part of the door so the cut edge of the door is visible. I can't find a functional reason for this; maybe it is necessary for some other types of installation? That's why you can see the bare wood in my photo (view from the outside of the door). After taking the picture, I covered it with Shurtape Indoor and Outdoor HVAC Butyl Film to seal it in, simply because I had that on hand.