So the Trollbyte sensor holder kit is designed to work excellent with it’s paralleling ring, but many customers are not using it correctly so they are having a bad experience. The key is that the parallel bar has a recessed location in the bar where you are supposed to slip the paralleling ring onto the parallel bar. They slip it on at the recessed portion but do not then slide the ring forward so it is very loose and may shift or fall off.

We made a convenient instructional video to show you that you want to slip the paralleling ring onto the bar and then slide it forward into position so it is tight on the holder set. Then slide the ring back to the recessed position before removing it.