In Star Trek: Voyager, what device does Seven of Nine use to regenerate?

In Star Trek: Voyager, Seven of Nine uses a Borg regeneration alcove to regenerate.

Borg drones normally spend several hours in regeneration alcoves instead of sleeping in conventional beds. The alcove supplies power and helps maintain the cybernetic implants that connect a drone to Borg systems. Seven retains this requirement after joining Voyager’s crew, although the ship modifies an alcove for her individual use.

Regeneration is more than rest. It is a maintenance process for Borg cybernetics and a way to restore the drone’s physical systems. Seven’s alcove is therefore both medical equipment and a visible reminder of her continuing connection to Borg technology.

The alcove should not be confused with a transporter platform or a communications station. It does not transmit a person or project an image. Its primary purpose is to support the biological and mechanical functions of an augmented Borg individual.