Just a little word of advice from your ole' uncle DirtBag for anyone in snowy areas & using their block heater.
Make sure the ends of each plug are reeeeeeeeeeeeeeeal real dry before putting them together......I realize this sounds stupid, but i went to plug mine in today and dried them both off with a towel until they appeared dry and i guess i was wrong, cuz it zapped the holy crap out of me.
On top of that I was standing in a puddle.....yeah, so that part wasn't so smart
Anyway, dry it off...ALOT..Before plugging it in if its wet out....hell put some gloves on if ya have to.
good luck
......i hate electricity