Are they going green or going gang?

You’ve seen them — those posters of celebs and New Yorkers of all backgrounds holding out three fingers horizontally to make a letter “E” and show their support for Earth Day New York’s “Be the E” campaign.

Actor Adrian Grenier and Jets star Darrelle Revis can be seen throwing up the E, too, in posters on subways and streets, along with a promotional video on the Web.

Their hand signs, though, strangely resemble those proudly displayed by gang members.

But despite the similarity, which the campaign’s creators laughed off, this symbol obviously has a far more positive message.

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Organizers of Eday40, part of Earth Day New York, hopes that message catches on worldwide.

“What the peace sign was in the ’60s, this is for this decade,” said Joanna Black, of G-Squared Group, which is helping to oversee the campaign. “It stands for the environment.”

Earth Day marks its 40th anniversary on Thursday.