The Bluesbox Collection The binding is both on the front and the back. These brass tuners are a clue to the dating - solid brass tuners virtually disappeared from the market after the 1920s. Dating is imprecise, however. The only thing for sure is that the guitar was built prior to 1941, because that is when Sears Robuck retired the Supertone brand name in favor of Silvertone. But it is pretty well documented that these guitars went out of production well before that date.