From the Pre Griswold era. See photos for all other references, to be sure this is the one you want. The item "Vintage Erie Griswold 11 B Cast Iron Skillet Heat Ring Antique Vintage USA PA" is in sale since Tuesday, February 20, 2018.
This item is in the category "Collectibles\Kitchen & Home\Kitchenware\Cookware\Cast Iron". The seller is "bs_stuff*2007" and is located in Hesperia, California. This item can be shipped worldwide.