Introduced in the San Francisco Bay Area in 2014, the Hook-Up Truck is the brainchild of Spy Emerson, a red-haired conceptual artist keen on making sex-on-the-go a possibility for all. Billed as “a modern dating solution for safe, sexual adventuring,” the Hook-Up Truck can be found parked at local, “non-aggressive” events, like Oakland’s First Fridays and St. Stupid’s Day in San Francisco, or it can booked for private parties. Lately, it’s been parked in front of the Albany-based dive bar, the Ivy Room, every second and fourth Monday, where use of the hallowed one-room space costs $50 for 30 minutes.

But it’s not just money that will get you through the door. Emerson also considers people’s personalities when deciding who to let into the Truck.

“If somebody comes up to me, entitled and privileged, with $100 bucks in their hand, I’m not going to invite them into my space,” she told OK Whatever. “If somebody comes up with nothing more than a handful of daisies and says, ‘Look, I’d really like to bang my girlfriend in here and I don’t have a donation,’ I’m going to give it to them. That’s the vibe I’m working on.”

The vehicle itself is a decommissioned 1987 U.S. Postal Service mail carrier, painted entirely white except for a heart on its side and the phrase “Make Love” emblazoned on its front. But though it’s obvious what the Truck is used for, its inner room — where the “magic” happens — is a mystery to all but those who have actually paid to rent it out. News anchors have tried to cajole Emerson into giving them a peak, but she’s stayed firm on her policy of showing it to “participants only.” She wouldn’t even give this reporter a glimpse of the Truck’s innards.

“It’s for people playing the game,” she said. “I’m not putting this on YouTube, like, trying to get clicks. This is a fun, sweet, total surprise, and no one has ever done anything like this before. So that’s why I have that rule. I want it to be unique for the people that actually partake.”