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x2 Lot SUN Vintage Optical Mice Mouse Systems Imsi PS2 DB25

These mice seem to be in great shape, but I don't have a Sun computer, so I can't test them.  As you can see, one has a PS2 connector, and the other DB-25.  One is Sun branded, and the other Imsi, but if you look on the bottom they both seem to be made by Mouse Systems.

I'm no expert, but my understanding is these are very early (possibly the first?) optical mice and that they probably need a special mousepad with a grid on it in order to get their bearings.

Very cool early mice -- I just have no use for them!

Let me know if you have questions!