FYI, get these center caps if you have the 21-inch wheel and want to run them without the aero covers:
Tire Wheel Automotive tire Light Vehicle

21" wheels, with aero covers, look not so great.
21" wheels, without aero covers, look great, but then you are missing the center cap (which is built in to the aero cover).
Rivian doesn't have a solution yet, but someone on the forum suggested some generic caps sourced from Amazon, and they actually fit and look pretty good!
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