Rare reverse type struck only at the Kyzikos mint.
Obverse: IMP C M AVR PROBVS P F AVG
Radiate, draped and cuirassed bust right, seen from rear.
Reverse: RESTITVTOR EXERCITI / V / XXI
Mars, holding spear and standing right, presenting globus to Probus standing left, holding sceptre.
Bilon, diameter 21,8 mm, weight 4,97 g.