Just checked my EDC flashlight magnet polarity and the makeshift compass performance:



A very flat neodymium magnet from an old HDD is epoxied to the back of the Photon REX (to magnetically mount it anywhere under the car hood, inside a computer case, and to other magnets sewed in my vest, hat, cap, gloves, etc.). It's orienting the On switch to the north in 3 seconds! And very reliably!