Tesla might have just released its coolest Easter Egg yet. As discovered by the Tesla community and confirmed by Teslarati this weekend, the electric car maker has released an Easter Egg on the Tesla mobile app consisting of several references to the Back to the Future franchise. The fun, hidden feature is accessible for Model 3, Model S, and Model X, owners, and is compatible with both iOS and Android devices.

Accessing Tesla’s Back to the Future Easter Egg on the mobile app requires some geek knowledge of the iconic, classic, sci-fi franchise. To access the Easter Egg, owners would need to tap the battery gauge on the Tesla mobile app. when the vehicle has 121 miles of range remaining. Once tapped, a message would appear onscreen featuring the first references to the Back to the Future franchise – “Ensure plutonium fuel is inserted into reactor chamber and press “Yes” to continue.”

Quite impressive in this new Back to the Future Easter Egg are the added details that references the iconic movie franchise. At the bottom of the mobile app’s screen, the vehicle will be listed as a Model X P88D, a clear reference to the 88 mph speed required for the DeLorean time machine to travel through time. The Version displayed on the app will also be listed as 1985.43, referencing the year where the original events of Back to the Future took place. Lastly, and perhaps most impressive, was the VIN SCEDT26T6BD005261 that is listed on the Easter Egg. A search for the VIN reveals it to be a DeLorean DMC12, the exact same car used in the movie.

With a ton of Back to the Future references, Tesla’s latest Easter Egg is most probably its geekiest yet. The added hidden factor, highlighted by its activation at 121 miles, makes it even cooler.