We had them at work they were a pain to fit and would fling off without warning and vanish into the darkness.
They’re for traction to get moving when stuck and then you remove them.
Not the autosox I used. They were fantastic a couple of winters ago when the snow hit Glasgow and the roads were crazy. Took about a minute to fit, and had them on for the 20 mile drive home. For anyone that knows the m77 the hill going up from Darnley was chaos, cars scattered and sliding everywhere, I had no issues at all.
They didn’t fall off, they were a very simple job to fit and they are very good.