I got this one:

https://www.amazon.com/gp/product/B00TO4MNSK/ref=oh_aui_search_detailpage?ie=UTF8&psc=1

The material is a thin cloth which feels like a cross between parachute material and Tyvek. It's thin and light but very fibruous like Tyvek is. But soft.

It rejects water "sort of". No water gets through it onto the car, so it's waterproof, but on the outer-facing surface if it rains, water only *mostly* sloughs off, not all of it. The last time it rained, I shook the cover really good and got most of the water off, then I bundled it up and put it in its bag. After it was in its bag for a while, the water all managed to pool up in the bottom folds of the car cover. So when I unfolded it, a bunch of water came pouring out.

The problem with the water is that if I want to dry it out I have to hang it up in the garage (taking up a lot of space) until the water drips down to the bottom folds, and then pour that out, and then let it gather in different folds, then pour those out, repeat ad infinitum. If I just say "fuck it" and don't bother, it gets moldy real quick.

What I'm wondering is if someone makes a car cover that is porous so that the water runs out on its own: I don't care if my car gets *wet*, I care if my car gets sap or other things dropped on it.

I actually intend it to protect the car in two places: Parking under trees at a friend's house, and parking in the garage next to Attoparsec's welding and machining. (My last car had thousands of microscopic bits of molten metal embedded in its windows.)

So I don't need the cover to be waterproof, just sap-resistant and able to deflect tiny bits of molten metal.

I've been searching on the 'net and can't really find anything.