Based on the illustration in the French installation guide I found online, double-sided tape and clips.How are they installed ? Similar to https://subaru.oemdtc.com/AccessoryInstallationGuide/F0010FL000.pdf?
well rain as you drive will enter w/o them also as you drive it does come in even if you have it open an inch you have no rain where you live then don't
These are great for when your car is parked in the sun all day long. Leave the windows cracked and if a random storm pops up you don't have to worry about the rain getting in. They easily drop the temp inside the car by 10 degrees as opposed to keeping your windows closed all day. I think they add a nice look to the vehicle as well. The Subaru ones are nicer looking than some of the other brands out there.As I've never been in a car with them, what benefit to they provide? Rain isn't a big issue where I live. Wind at speed? I rarely open my windows - long hair and windows get problematic. I had the moon roof deflector on my Outback and it really cut down on the air movement within the car. Only negative was washing the car, the deflector caught the water and it made keeping the area clean a bit tougher. Just curious as to what the main benefit of these deflectors are???