Are you one of those types who has been driving in the recent chill with frozen screenwash praying the heat from your engine will eventually defrost it? Perhaps you have been using readymix or the cheapest crap money can buy. If you'd rather it wasn't frozen, buy a few bottles of this before it sells out. It's good to -60 degrees undiluted (many ready mixes/cheap stuff is only rated to about -5 degrees). This sold out of most stores quite quickly last time it was on offer and I think it will sell out even faster this time.