This is one of those products that I wish I knew about years ago when I was still working in the shop! I would have used these thing on virtually every set, and in a lot of props. A switchable magnet uses 2 or more magnets that are aligned with their poles cancelling each other out. A physical knob or lever changes the position of them so that the fields work together and stop cancelling the magnetic force. These products are often used as guides for wood working, material handling, clamps a...