The Dymo label at the top of the case reads DISCONNECT CAPACITOR DRIVE BEFORE OPENING.
The capacitor drive was a component of the flux capacitor, the device that caused, along with the stainless steel construction of the DeLorean time machine, the dispersal of flux energy, which made time travel possible.
A Dymo label at the top of the case containing the flux capacitor warned that the capacitor drive had to be disconnected before opening, while a second label across the glass panel read SHIELD EYES FROM LIGHT.