51 Hours is a song recorded in mid-April 1992, by Lori Elle (Werner) (as 'Diamond') and Robia LaMorte (as 'Pearl'), at Studios 301, Sydney, Australia (during the Diamonds And Pearls Tour).
The music for the track was written and recorded by Australian techno producer Mark Forrester and synth programmer and engineer Angelique Cooper. According to Cooper, "Mark Forester (and her) were messing around with a dirty synth line when Prince walked into the control room from the Studio. He loved the synth line and they continued to build the track up over the next 24 hours." Angelique & Mark were brought back to Paisley Park with him to complete the track. Together, they "worked the music bed up over the next week. Prince came up with the lyrics and ultimately decided to use it as a single to launch the career of Diamond and Pearl. Some of Prince’s demo vocals remain on the final version."
Carmen Electra is also believed to appear on the track’s vocals.
The song was played on a Spanish radio station during the Summer of 1992, and was said to be due for release after the Diamonds And Pearls Tour. Prince had around 20 copies of an in-house 12" vinyl, 51 Hours, pressed, containing a longer version of the track, but the copies were not officially distributed and the single remains unreleased.