The EV-series medical droid, also known as the A-series medical droid, or the A4 laboratory assistant droid, was a model of medical droid based on the EV-series chassis that was manufactured by MerenData. Beginning their operational lives as EV-series supervisor droids, the company refitted them as cheap medical units in an attempt to salvage the EV-series.[..] The Confederacy of Independent Systems purchased and retrofitted an EV-series medical droid designated EV-A4-D, gifting him to General Grievous to serve as the cyborg’s surgeon and cybernetics repair technician.
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