okay I understand supply and demand. I guess I would assume all the cars bought new would have one. and most of the cars bought used should have one. so that leaves one each from all the wrecked cars that would be available. and also there might be some that are still in new old stock.
my car didn't have one when I bought it. seems to me that people needing one, like me, would be far fewer than ones available from wrecked cars and GM. therefore demand should be less than supply. or at least that's my opinion anyway. Thanks for participating with this discussion.