They have been very useful to me both for their intended purpose and for other purposes. There are many great mounts and accessories out there for 3D printing, so they come in handy even if you're not into industrial automation.
Vacuum cleaner KARCHER VC 3, yellow
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Universal Rotary Cam Selector Latching Switches - VictorsHome Changeover Switch LW28-32 With 3 Positions, 12 Terminals For 690V, 32A Capacity
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TWTADE/AC 24V 10A Coil Electromagnetic Power Relay 8 Pins 2DPT 2NO+2NC With Indicator Light And Socket Base -YJ2N-LY
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Adjustable Regulator Generator PEMENOL Controller
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