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magnetics - Magnet that needs power to turn off? Inverse coil? - Electrical Engineering Stack Exchange
![Adjust-O Magnetic Square, On/Off Switch, Max Pull Force: 65 lbs (30kg), 45° & 90° Angle, 4-3/8 x 3-3/4 x 1″, Patented Design, MSA45, Strong Hand Tools - - Amazon.com Adjust-O Magnetic Square, On/Off Switch, Max Pull Force: 65 lbs (30kg), 45° & 90° Angle, 4-3/8 x 3-3/4 x 1″, Patented Design, MSA45, Strong Hand Tools - - Amazon.com](https://m.media-amazon.com/images/I/81Rvkax5eAL.jpg)
Adjust-O Magnetic Square, On/Off Switch, Max Pull Force: 65 lbs (30kg), 45° & 90° Angle, 4-3/8 x 3-3/4 x 1″, Patented Design, MSA45, Strong Hand Tools - - Amazon.com
![Adjust-O Magnet Square, Heavy Duty, On/Off Switches, Pull Force: 65 lbs, 4-3/8" x 3-3/4" x 1-1/8", MSA46-HD, Strong Hand Tools: Magnetic Sweepers: Amazon.com: Industrial & Scientific Adjust-O Magnet Square, Heavy Duty, On/Off Switches, Pull Force: 65 lbs, 4-3/8" x 3-3/4" x 1-1/8", MSA46-HD, Strong Hand Tools: Magnetic Sweepers: Amazon.com: Industrial & Scientific](https://m.media-amazon.com/images/I/81vtCwAaJwL.jpg)
Adjust-O Magnet Square, Heavy Duty, On/Off Switches, Pull Force: 65 lbs, 4-3/8" x 3-3/4" x 1-1/8", MSA46-HD, Strong Hand Tools: Magnetic Sweepers: Amazon.com: Industrial & Scientific
![magnetics - Magnet that needs power to turn off? Inverse coil? - Electrical Engineering Stack Exchange magnetics - Magnet that needs power to turn off? Inverse coil? - Electrical Engineering Stack Exchange](https://i.stack.imgur.com/9zWhM.png)