The universal translator device is a device that appears in the episode "My Two Favorite People." Jake originally wanted for him, Finn, and Lady Rainicorn to hang out together, but an evident problem was that Lady Rainicorn only spoke in Korean and Finn couldn't understand her. Jake mentions that he had previously thrown the translator into a lake. The trio then go to retrieve the translator from the bottom of a lake, which was guarded by Lake Knights. Ultimately, Jake takes the translator off of Lady Rainicorn and throws it away after Finn wins his battle with Tiffany.
For unknown reasons, they wear these translators at all times, even when in the Crystal Dimension, where they would be unnecessary.
The universal translator device appears to be similar to a dog collar with a brown strap. The translator itself has a red checkered switch lever, pieces of tape listing the settings of the device, the speaker, and the knob to select the setting. The tape labels read: Old Man, Nerdy alien, and nightmare.
The settings on the translator are "Nerdy Alien," "Nightmare," and "Old Man." Finn and Jake had to set it to Old Man because it was the only setting in which Finn could understand Lady Rainicorn even though he found the others to be entertaining. While Lady has the device on her, Finn jokes around and occasionally calls her, "Grandpa." The first time Jake was talking to Lady Rainicorn with the old man voice setting he accidentally calls her a him. However, the translators of Bob and Ethel Rainicorn have normal voices.
- All three of Lady's translator voices were provided by Pen Ward.