"My cat loves to hide from the dogs in the den. Until I got this cat flap for the door, she'd just paw at the door knob till someone let her in/out. Even if that meant waking someone up!
I checked out the directions for several cat doors, but most seemed to complicated to mess with. I was a bit leery about using the jigsaw as I hadn't done that before, but just took about 20 minutes to get it all done. I wouldn't get a great grade for staying on the line when I cut, but it worked.
It was a hollow door I cut through, so I duct taped the inside of the hole before putting on the flap.
Kitty took two or three days to go through on her own, but now does so with no trouble. The dogs nose the flap open sometimes but it's too small for them to get their heads in.
I haven't tried the lock and most likely wont. We got it so kitty could go in and out as she pleases."