Watch List notes:

Ptolemaic Kingdom. Ptolemy II Philadelphos. 285-246 B.C. AE 28 diobol (28.49 mm, 14.01 g, 12 h). pre-reform coinage, pre-centration. Alexandria mint, ca. 280-60 B.C. laureate head of Zeus right wearing horn of Ammon / ΠTOΛEMAIOY BAΣIΛEΩΣ, Eagle standing left on thunderbolt, wings open, head left; in field, Σ / shield; between legs, I / trident countermark on eagle's left wing. Svoronos 577. near VF, nice, clean and clear countermark. 

The pit in the reverse is not a centration dimple