Dated Roman Egypt billon tetradrachm, 6.73g, Emmett 4147/7 (does not reference the date error).
Minted in the 7th (L Z) Alexandrian year for Maximianus which corresponds to A.D. 291/2. Note that the date letter, Z, is retrograde, a mint error! The mint workshop is indicated by the Beta (B) below the ex. line.
Certified by NGC to Ch VF.
Reverse Nike flying right holding wreath and palm. Nike was the goddess of victory in Greek mythology, depicted as having wings, hence her alternative name "Winged Goddess".