Magnetic Polarity Tester with ±5mT Sensitivity, One-Button Operation for Electric Motors/Coils/Magnets Assembly - LED N/S Detection Pen, Portable Gauss Meter with 10-Hour Battery

The sensitivity is high. I compare it to a 14mT tester, and it detectes way smaller magnets

Works exactly as intended. I had a very expensive gauss meter which failed to give easy to read measurements of a series of 20 magnets lined up in a row, simply testing to see if they were installed in the right direction. A simple red light / green light worked surprisingly well.

This product works good in what is advertise it but just only check polarity not test the amount of gauss in the magnet.

I have more magnets than ever now, and they are very useful generally; but for some applications you need to identify the North and South poles and their orientations to properly install the magnets correctly. This little tool lets you identify the orientation, potentially saving you a bunch of time.

What I like about this polarity tester is the size. It is easy to hold in your hand an easy to understand. Thank you for reading my review. May God bless. May the rest of your life be the best of your life. OZ

I have not bought this product, and I don’t doubt that it probably works as intended. But WOW… OVER-engineered and OVERpriced, when all you need is a simple magnet. Basic physics test: If you want to know an unknown magnet’s polarity, just expose it to another (weaker) magnet whose polarity is already known, like a cheap (~$5) stick magnet whose ends are already labeled with N and S. (And you can confirm the N/S accuracy with a compass, if needed; like with the Earth, the compass points toward N pole of magnet.) >If the known magnet S pole is DRAWN TO and N pole is REPELLED FROM your unknown metal surface, then that surface is the unknown’s N pole (opposites attract, sames repel). >If N pole drawn to and S pole repelled, then the unknown metal surface is the unknown’s S pole. >If BOTH N and S poles are drawn to the surface, then the unknown metal surface is paramagnetic, like your fridge door; a magnet can stick to it, but the surface has no permanent polarity. Lesson over. Happy shopping.

Excelente producto, gracian calidad y precio