Would one of y'all experts be able to confirm is this is an unmarked Erie Series 2 #8 skillet? It is so light and so far my favorite to cook with, so now I wanted to know what is was. Also, in the 3rd picture, what are those ridges (grips of sorts?) notched into the side of the handle where it meets the pan. Is Erie (if this is one) the only manufacturer who used those notches?