Probably not the type you are asking, but I used to repair old (aka ancient) DTS 500 cash registers for a living about 30 years ago.
Back then, the keyboards used reed switches for each key on the keyboard and the key locks as well.
These were in very busy grocery stores and I maybe replaced a dozen that went bad (stuck) in those 15 years.
I must have soldered thousands of them to create new keyboards from old parts, this was the only way we could repair them as we bought old registers in bulk as spare parts.
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