Rick, yes, thats why they are shaped that way, so you take out the two eyes, and the I, if I had an I with a top and bottom, and then the sad iron heater fits right in the opening that is created, if its a number 8 sad iron heater, it will fit a number 8 hole. Also, the ham boilers that you sometimes see, a lot of them are gatemarked, same thing, they are made to fit them holes. And they are also used to boil water or whatever.