They say they're trying to spread peace around the world by connecting strangers with one another -- starting with a simple request:
"Can you join us? We're about to take a picture for peace," Manuel Frederick asked the passing crowd at San Francisco's Pier 39.
They've made that request over and over -- at the Golden Gate Bridge, at Stanford, and at countless iconic spots in all 50 states.
"It's all about bringing people together, because we're not all the same, we're all different, but we should all treat each other equally," Frederick said.
He and his co-founder Andrew Tisba began their quest in Europe two years ago.
"Two terrorist attacks in Paris, with the whole refugee crisis, especially in Germany, and I'm from Germany, Andrew's from France," Frederick said. "And we felt we have to get active and do something."
That "something" was a simple gesture: standing with arms crossed, your palms touching the people on either side of you, and uttering an almost-melodic "mmhmm!"
"Bringing people back in touch with each other, you know?" Frederick explained to a small group who had gathered out of curiosity.
It doesn't take long to catch on. Within a few minutes, they'd gathered a line of several dozen people willing to "connect" for a photo opportunity -- and also connect in real life.
"I like your tattoos," remarked a pink-haired woman from the Bay Area to the man from Australia standing next to her.
"Thank you very much," he said. "I love your hair!"
The Connect Guys call the hand gesture and its accompanying sound "human connectivity." It's different from digital connectivity, they say -- and when you're physically connected to the people on either side of you, you don't have a free hand to hold a phone. Instead, you might find yourself engaging with people from different cultures or different continents.
"i'm from Canada, I'm Alisa," one woman said to the man next to her.
"Hi, I'm Paul from England," he replied.
A teenager piped up, "That's awesome, i didn't expect any of you guys would be from England!"
"We were all strangers but we all kind of connected for a few minutes," said Erika Mendoza, who's from Redwood City.
As the Connect Guys have traveled the country, they've connected with countless strangers as well as a long list of important Americans. Senators Kamala Harris and Elizabeth Warren, TV hosts Anderson Cooper and Andy Cohen, Actor Colin Farrell and the mayors of Chicago and San Francisco are among them.
"People connect but it's fast, you know -- you click," Tisba said, high-fiving Frederick with a sound vaguely evocative of a mouse click. "We say don't click -- we connect, you know?"
They proceeded to demonstrate the "connect" gesture again, complete with "mmhmm" in unison.
Posing for the camera, the crowd chanted: "We are connected! -- For what? -- For peace!"
Afterwards, Corrie Herborn, visiting from Australia, remarked: "We were so comfortable together. Yeah, that's what it's about isn't it?"
The Connect Guys said they planned to leave the Bay Area on Wednesday to head back to Los Angeles, where their 50-state tour began. They said they were holding out hope that Facebook founder Mark Zuckerberg would invite them to "connect" with him before they leave.
Click here for more information about the Connect Guys.