Ideal Screen-Fit Cat Door
This cat door consists of a strong, clear ABS plastic flap embedded in a plastic frame.
What strikes us as interesting about this flap is that it isn't screen. The problem with screen is that we think a scratching cat trying to get in when it's locked is likely to tear screen. If this ABS plastic is strong enough, however, it might prevent that problem. We're looking forward to the first customer review to address this point.
Installation is easy; you only need a sharp knife or box cutter to cut the screen using the frame as a template. The cat door then snaps together. The instructions clearly state that it must not be installed lower than 3" above the bottom of the screen frame. This is because the door needs a bit of lag in the screen to serve as a sort of shock absorber. If the cat door is installed in the tighter part of the screen that is close to the frame, it will be easier for the cat to tear the screen while travelling through the cat door.
Support is from the screen only so it matters what kind of screen you've got. A genteel cat combined with strong, wire screen would be the best combination. Speaking of size, the box claims 9 3/4" x 10 1/2" flap dimension and suitable for cats to 20 lbs. We measure 8 3/4" x 10 1/4" but, either way, the opening is plenty big for even the biggest cat.