Rob Reiner's Spinal Tap scene inspired Elon Musk's Tesla

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“These go to 11.”

The classic This Is Spinal Tap line was completely improvised, just like the rest of the mockumentary which launched the genre.

“That now has become part of the vernacular,” Rob Reiner told PeopleTV’s Couch Surfing host Lola Ogunnaike about the immortal moment when Christopher Guest’s fictional rocker, Nigel Tufnel, explains to Reiner’s character that their amps are specially designed to go “to 11” for extra intensity.

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But how do you know when a movie moment has truly transcended the cultural consciousness? When Elon Musk adds it to his Tesla design, of course.

“When Elon Musk first created the Tesla, I was at a party, he brought this car in,” Reiner recalls. “He said, ‘Let me show you something.’ He sits me down in [the Tesla], shows me the radio, and the thing goes up to 11. That was like the coolest thing.”

Watch Reiner recount the crazy run-in with Musk in the Couch Surfing clip above.