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Name: Dennis G.
Status: Other
Age: 60s
Location: N/A
Country: N/A
Date: June 2004
Question:
How long have polarized outlets/plugs been in use in the U.S.?


Replies:
I regret that I do not know. This is a history of technology question and the answer might be found on the Internet.

Bob Erck

Dennis,

The two wire (nongrounded) receptacle is found only in older houses built before the mid-1960's in the United States. I hope that this is sufficient.

Sincerely,

Bob Trach


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