Someone wrote to ask what kind of trap I was using. It's a Havahart (that's the brand name) model #1045. You can read all about it on this page. As you can see, there are doors on either side. You fold them upwards and then the door is held open by a little rod that connects to another rod that connects to the floor panel. When the cat (even the wrong cat) steps on the floor panel, the rods move, the one holding the door open disengages and the door slams shut, trapping the critter within. It reminds me a lot of how I wound up working for Hanna-Barbera all those years.