A man laughed and joked as his girlfriend performed a sex act on him while he drove down a busy motorway.
The driver, known only as Billy, was filmed by a pal as the dark-haired woman pleasured him while cars passed by in the next lane of the M1.
She is believed to have been sitting in the middle of a three seater van when she placed other motorists in unimaginable danger for the outrageous stunt.
The footage was captured by an unknown pal, known only as Jimmy, in the other passenger seat.
At one point he boasts: "We are on the M1."
Billy is described as traveller during the lewd commentary during which the woman gives the camera man "the finger" before continuing to perform the sex act.