Float switches that can be submerged

[110galreef]

Seems most all are not to be submerged.
What is everyone using for these. I want to put one in my return section as a saftey to prevent running dry.

 

[allsps40]

My JBJ floats are submerged all the time. One is always under water, it is my low level top off float. It is at the bottom of a 5 gallon bucket full of kalk top off water. I have no issues.

 

[mozz]

This is the way I submerge mine