used AC, a neatly written-up study matched with the perforated issues, illustrating the varying stages of wear and the repairs to this position, comprising imperforate State 1 (2) without wear, State 1 with light wear, perforated 16 State 2 (2) re-engraved, State 2 with light wear, perforated 14 State 2 AC-AD pair with heavier wear, State 3 (re-entered); lightly or neatly cancelled and mostly fine. A rare group