Seems like I've been acquiring a lot of these Brother dome over membrane keyboards lately. Typing wise they are actually pretty nice for what they are.
The keycaps are dyesub (though a bit more feathering then usual). And unless this is a freak of nature, looks to be PS/2 (not sure if the wiring of the SDL is same as Model Ms, but it likely is).
Keyboard itself was made sometime in 1990.






















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