Just two months after its official unveiling, the Tesla Semi is really really real.
A UPS worker in California last week captured the first known footage of a Semi in action, rolling through Sunnyvale, California. The clip is brief, but revealing.
Most obviously, that’s a pretty quiet truck — as one commenter put it, it’s “what the future sounds like.”
CleanTechnica did some additional digging, and says the truck was likely traveling between Tesla headquarters in Palo Alto and Tesla’s factory in Fremont, where the company manufactures Model S, X, and 3 cars.
Get Data Sheet, Fortune’s technology newsletter.
Teslarati further speculates that the truck could be deployed as part of Tesla’s own supply chain, based on prior statements that the company would be using its own product. Also notably, the truck captured in the video has side mirrors, likely because regulators haven’t yet approved the planned camera system that will replace them in production models.
It’s also worth noting the amazing coincidence that the video was captured by an employee of UPS. The shipping company has already placed an order for 125 of the trucks, still apparently the largest single order on the books. This video — of a truck that’s not going to reach customers until 2019 — certainly makes that look like a solid bet.