I'm just forwarding this post from yaktx

"How can they continue to sell stuff like that if it's not legal to use?"

Legacy of a chicken/egg question, circa 1959.See the bullet point, "Ideal for inclusion in kits for portable electric tools or equipment having 3-wire grounding caps." Adapters like this were a compromise,it seems.

Note that they do provide grounding if one actually bothers to connect that pigtail to the coverplate screw. And connecting it may not help if you haven't verified the availability of a ground. Anyone who knows how to do that knows how to replace a receptacle, right?

Incidentally, they did away with that whip of a green pigtail some years back, since if left hanging (as most of them are), it can contact the hot blade of the plug and energize the frame of the appliance (!!!) All
new cheaters have that little fixed fork. Kinda hard to run that around to an exposed ground screw on the lighting track, isn't it? (Assuming one could be found.)

Legal to use and legal to sell are two different things, I guess.

--yaktx

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