Don't buy this, use other things for multi-camera
For IVPort Raspberry Pi Camera Module Multiplexer
The multiplexer has never work for me. I tried the multiplexer and I think than I accidentally do a short circuit that has burn the chip and one of my Pi camera (the second was correct). It seem like normal than it's doesn't work, as we can see on their GitHib in the "issues" where only 4 of them has been resolved and a lot of peoples than have the same troubles. A person have also open a other GitHub to try to do reverse engineering to see why it's doesn't work.
Seriously, don't buy this and chose a other method to have multiple camera, like using a other type of board (like the "Raspberry Pi Compute Module I/O Board" of Adafruit) or use multiple USB/IP camera or any other type of camera. Personally, I choose to have one Pi Camera and multiple USB camera for my stereo system and it work very easily without any problem.
