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THAT receptacle will look funny to those with good eyes. That is because this receptacle has a standard 120 pattern on the botton, and a 220 v. pattern above.

Those combo receptacles are still available.

[Linked Image from hubbellcatalog.com]

But I would not suggest using it like this.

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The 120 part, where active (not every room is) is powered from one leg of the heater circuit, and uses the conduit as a "neutral."

Bob Badger
Construction & Maintenance Electrician
Massachusetts