If memory serves, that looks like the Gemini Upgrade Card, known by other names, Gemini might be the one Total Systems used, dunno. Somebody here posted info including pics and the name of the OEM. A friend had one back in the day, the extra is addressed as VM under Compact Virtual, IIRC.

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Odd SE/30 card?

Quesse Total Systems PDS accelerator for SE

Quesse, that's it! Check for that brand name or any other etched verbiage, likely on the solder side of the board.