Has anyone used "Flood Guard" for basement drains?

[Rob K.]

We recently had massive flooding in our area due to an ancient infrastructure combined with massive rain. Thousands of basements were flooded. I recently heard about this product and purchased a few. I'm curious if anyone has ever used it and knows if it works?

You drop it in your basement floor drain and turn the four screws. The rubber ring gets compressed and forms a seal inside your drain pipe. Water can go down, but if sewage starts to back up, the hanging rubber ball rises and forms a seal to prevent sewage from coming into the basement.

It sounds good in theory. Any feedback would be appreciated.