This blowout plug made winterizing a breeze. Drain the water heater and fresh water tank. Hook this up to the fresh water connection, set the compressor regulator to 30-40 pounds, open the taps and let the water blow out. So much easier than trying to get antifreeze in the lines. And easier to de-winterize next season. About $8 from any supplier makes it cheaper than antifreeze, too.
Winterizing made easy