Hot Water Tank Anode Bolt

I used to use my 1-1/8" socket to remove the anode, thinking it must be metric because the socket was a little sloppy. I finally realized it takes a 1-1/16" socket ($4.00 at Home Depot).
I also learned the hard way to relieve the pressure on the tank before removing the anode. I did this on a old pop up camper I had and luckily I was standing up and didn't have my face down in line with it.......It hit me right in the gut full force..Ouch!! I won't do that again!!!