I thought I'd give this a test to see how water tight these rivets are, so I setup a little water reservoir with a rivet at the bottom, I'm sure it's not rated to IP68, but over 24hrs it didn't leak any water, not a drop (obviously you can't see the water because it's transparent!!), the car won't be sitting in water for a day, ever, but if it is I suspect I've got bigger problems than a bit of water ingress ... saying that I will probably seal the underneath of the car anyway
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