Have you ever dropped a bunch of nails or screws in your yard and thought, "How can I find all these things?" Magnets to the rescue! Magnet cleaners use magnets to pick up ferrous materials like nails, screws , nuts and bolts. They are very useful in the house or workplace to help prevent punctures or damage to machines. But what should we pay attention to when we buy magnetic sweeper? I hope the following points can help you.