This is a small tool I use to solder power cables

You can use an iron ruler to fix it

The bottom is connected by screws, which is very sturdy

Internal spring with a wire diameter of 0.7mm and a diameter of 6mm, and a length of 25mm. This depends on your own needs. My maximum opening setting is 10mm.

The diameter of the bottom magnet is 10mm, and its thickness is 3mm.