ULIBERMAGNET 4Pack Anti-Scratch Neodymium Magnet with Rubber Coated and M4 Female Thread,Super Strong Magnetic Mounting for Lighting,Camera,Tools and equipement: Amazon.com: Industrial & Scientific
Reference Magnet For Gaussmeter Tesla Meter Magnetometer 790 Gauss +/- 2% | eBay
ULIBERMAGNET 2Pack Rubber Coated Magnet with M6 Female Thread Stud, Anti-Scratch 60lb Strong Neodymium for Camera, Outdoor Light Bar, Signal Lights and Tools: Amazon.com: Industrial & Scientific