This video is pretty incredible. It shows how the more than 28,000 footballs used in an NFL season are handmade and inserted with inflatable bladders.

From hand-stitching to an “inflatable bladder,” this whole process is really cool to watch. As you can see, the footballs are inflated to 13 PSI prior to leaving the factory. What happens beyond that point, I guess we’re still trying to figure out.

On a side note, deflated footballs REALLY have “bladders.”