A rover without its wheels can’t do much roving at all, so the recent addition of fancy new wheels to the Mars 2020 rover is pretty exciting for NASA and space observers around the world. In a new blog post, NASA shows off some awesome photos of the wheels that were just affixed to the robot in the testing lab.

The wheels, which are made out of aluminum, are quite large compared to those of some of NASA’s past rovers, giving us a nice point of comparison to gauge the difference in the overall size of the robot itself. However, as lovely as these new rover shoes look in the lab, they aren’t fit for duty on Mars.

As NASA explains, the wheels that were just added to the Mars 2020 rover won’t actually see duty on the Red Planet at all. They’re engineering models made for testing, and NASA will still need to swap them out for the “flight models” which will make the trip and eventually crawl across the dusty Martian surface.

NASA offers some stats that give us an idea of how advances these wheels truly are:

Made of aluminum, each of the six wheels (each 20.7 inches, or 52.5 centimeters, in diameter) features 48 grousers, or cleats, machined into its surface to provide excellent traction both in soft sand and on hard rocks. Every wheel has its own motor. The two front and two rear wheels also have individual steering motors that enable the vehicle to turn a full 360 degrees in place.

The Mars 2020 mission won’t lift off until July of next year, and won’t actually arrive at Mars until early 2021. Still, the mission team is already seeing the fruits of its labor pay off in the impressive machine.

“Now that’s a Mars rover,” David Gruel of NASA’s Jet Propulsion Laboratory said in a statement. “With the suspension on, not only does it look like a rover, but we have almost all our big-ticket items for integration in our rearview mirror — if our rover had one.”