CMS Magnetics - Magnetic Pole Detector, a Handy Polarity Identifier to Determine Magnet's North or South Poles, Great for School Teachers, Science Projects, and Metal Detector

This product perfectly tracks the pathway of a magnetic field from one pole of a magnet to another. It also works great for locating the poles on a piece of magnetite. I have a chunk of magnetite that has four poles, and it quickly finds and identifies them. It would have to be a very powerful magnet to identify the pole from a couple feet away. I have a 6" x 1" bar magnet, and it picks that up a foot away. But to show the magnetic field is parallel to the body of the bar magnet it needs to be about an inch away on the sides. I go past the end of the magnet a couple of inches and it definitely shows the field orientation. If the magnet in this sensor gets stuck to a bigger magnet, use care separating the two. Slide the sensors magnet to the edge - don't just yank it off! The product advertising does state that this device is 4.75" long, but I missed that. When I opened the package, I was expecting something a bit longer, but that's on me. The compact size does not detract from the operation at all, and it does make it easier to slip into a shirt pocket. This product is a delicate instrument and should be treated carefully. This is not a defect, pivoting a magnet in two axises requires some small parts. Treat it carefully and will reward you with years of service. Give it to careless kids and it won't last. I like it and will order a couple more. I think you will like it too.h

Every 3d printer enthusiast who uses magnets in their prints needs to know these exist. I've wasted so much time trying to figure out which side is which on my magnets and this solves it with a single quick glance. It's nice and compact and feels quite sturdy.

good to know where your at

Moves when close to magnets. Doesn't work as compass.

Until I got this little gadget. At first I was using the earth to determine which way was North and South on the magnets like a compass. But apparently I swapped a couple around or the magnet wasn't strong enough to straighten itself out with the magnetic pull. Now I just use this and I get it right all the time.

This thing is like 5-6in tall and 3in wide at the top. I thought it would at least be a little bigger than that. So... A little disappointing for that reason, but it works, I think... It's not amazing. It clearly is a $2 item at most if you were to buy it locally, probably a 50cent item to make. Underwhelmed to say the least. Also the magnets aren't labeled with an N or a S, just assumes you know Red = North and Blue = South. Also, for a company that brags about their Environmentally friendly status, this thing came in a large box with a "WARNING MAGNET" label for something that has less gauss than a button cell battery, there's no way this was affecting any sort of avionics or magnet sensitive equipment. Could barely hold a sewing needle.

Inexpensive, but I will need to find a box to put it in.In an interesting way it also identifies to a certain degree just how strong the magnet it.It snaps for strong batteries and you can also read its magnetic field as you move it away from the magnet. It was very interesting. Glad I bought, but I do need to find a better safe keeping spot for it...

North is south. Junk