Review on Defender Security 9895 Viewer Plastic by John Talcott

I'm a scientist so I take the whole phrase "measure twice/cut once" to a ridiculous level. I measured my door every way I could think of. It didn't fit my door. Oh, the diameter was ok. But the thickness of my door was a little (scientific term - no doubt) too big. The problem was that the threads on the device didn't run the full length of the eyepiece. yes i could pass but seriously, it should have worked. Anyway, I found the best option with a "lid" that prevents "look back" and this option fits perfectly. I only wish these manufacturers would add a little more kick to the rating. In fact, how much harder would it be to cut threads a little further on the machine? Do you know how full the pipe length is? I gave it 2 stars because I'm sure it worked great on other people's doors.