Watch List notes:

Domitian (81-96), Accidentally incuse As, Rome, AD 90-91; AE (g 12,64; mm 27; h 12); IMP CAES DOMIT AVG GERM - COS XV CENS PER P P, laureate head r., Rv. Incuse of obverse. Cfr. for the obverse RIC I 394-397 = II 707-709.
A very rare incuse, brownish patina, very fine.