"Just like the big red STOP button you'll find on every table saw, drill press, etc." For those that like finding out, "What's the formal name for that?"... it

"Just like the big red STOP button you'll find on every table saw, drill press, etc." For those that like finding out, "What's the formal name for that?"... it's called a kill switch: https://en.wikipedia.org/wiki/Kill_switch https://en.wikipedia.org/wiki/Kill_switch For further reading, see the related "Dead man's switch": https://en.wikipedia.org/wiki/Dead_man%27s_switch https://en.wikipedia.org/wiki/Dead_man%27s_switch