When I get my new car that's the first thing I'm getting if it don't already have one. My last car had it and it was everything on days like this. This morning I was layered up just to go warm up the car... my case of water in the back seat was frozen!! Like yeah I know it's 4 degrees but be realization sets in when you see your water frozen & it's not in a freezer.I had it parked outside all night. Ran the automatic starter while I was getting ready and it still have me a false sense of hope