Watch List notes:

PTOLEMAIC KINGS of EGYPT. Ptolemy II Philadelphos. 285-246 BC. Æ Tetrobol (34mm, 37.03 g, 12h). Alexandreia mint. Series 3. Struck circa 261/0-246 BC. Diademed head of Zeus-Ammon right / Eagle standing left, wings spread, on thunderbolt; Ǝ between legs. Svoronos 448 var. (E not Ǝ); SNG Copenhagen 153 var. (same). Near VF, rough tan surfaces. Apparently unique with Ǝ control mark.

Cathy Lorber notes that while this retrograde E control mark is not recorded, variants are known for other denominations in this series.