Could this be . . .the elusive LONG DISTANCE creb? Clearly marked with SN 10. . .to the right. . .the letters LD.
Just kiddin with y'all. . .looks like a bit of jumpin around in the mold caused this interesting defect. . .why it is a good idea to look at all the cheap stuff in the box. . .may find a pleasant surprise for a simple mind like mine.