A miniature version of the usual rectangular panel mount rocker switch - I saw these on a USB hub (for switching off each port individually) and just had to get some in, they are, well, too cute for words.
SPDT - Single Pole, Double Throw, aka On-On or A/B, that is, the center pin is common and "throw" up to connect to one end pin, or "throw" down to connect to the other end pin. Note that there is no center-off position, it's either A or B, there is no C.
The bezel is 15mm by 10.5mm, the rocker itself is a diminutive 6.3mm x 9.83mm
You will need a rectangular hole in your panel about 12x9mm, there are the typical springy tabs to lock it in with a push-fit.
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