Once the plasterboard it mounted over the steel beam, it is practically impossible to find the metal again and put screws into it.
That's where my tool comes in handy! The CSN-48 finds the metal easily and you can just let it hang there upside down.
The CSN-16 holds a nice stockpile of screws within reach that you can use to screw the plasterboard onto the steel beam.
That saves a lot of time and the painter doesn't have to paint over marks on the plasterboard.
Thanks a lot, supermagnete!