Key switch

A key switch is a switch that can be activated only by the use of a key. They are usually used in situations where access needs to be restricted to the switch's functions.

Key switches are available as components with solder connections, and are available with a variety of ampere ratings. They may use tubular or other specially-shaped keys for extra security.

Key switches have been used for a variety of purposes, up to and including the launch of nuclear missiles.

In less secure applications such as corridor and restroom lighting controls in public buildings, tamper-resistant switches with a simpler key mechanism may be used instead.

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