The one's I have need to be loosened/tightened using a wrench each time
you want to use them. I find them to be quite useless when they are up
as the machine's vibration is enough to loosen the nut holding them up,
and constantly causing them to drop. fuhgeddaboudit!

Yes, I have them. I stole the ones off a single stage I trashed and
put em on my new (used) 2-stage. They work great. Yes, the snow does
fall on the machine but so what...it is built to take it. I have had
enough fall to short out the plug but just clear it away, fire up
again
and back to work.

Harry K