I bought these to protect my car from the sun and still hold the numerous suction cups on the inside of the windshield. Between my phone charger and the dash cam, I was no longer able to use a regular sun visor. The device is easy to put on and held securely in place with magnets, side tabs and elastic straps. I'm afraid the rubber band will break over time, but we'll see. The only downside might be that it doesn't fold easily. Haven't used it yet in winter but I'm sure it will be good. for that too.