Google’s autonomous car project is marching on after hitting a new milestone: the company’s fully autonomous Toyota Prius was formally registered in the state of Nevada as an autonomous vehicle, allowing it to operate on Nevada’s public roads. Last year, the Nevada Assembly passed legislation that paved the way for the state to be the first in the nation to formally license autonomous vehicles (as opposed to just licensing a vehicle) within the state’s borders. This month, the state debuted a new type of license plate for autonomous cars–a red plate with an infinity symbol on the left side of it and the first two digits spelling AU–and gave the AU-001 plate to Google and its Toyota Prius. Google’s autonomous Toyota Prius, along with a handful of other self-driving cars, has been testing for some time now in California, but Nevada statutes now formally recognize autonomous cars and regulate where and when they can be tested. While the cars drive themselves, Nevada law stipulates that they must have two passengers–one in the driver’s seat and able to take over the controls, and another in any other part of the car.