Probus AE Antoninianus. Rome. AD 279. 

IMP PROBVS AVG, radiate, helmeted, cuirassed bust left,
holding spear and shield.
ADVENTVS AVG, Emperor riding left, right hand raised, left 
holding sceptre; at foot, captive. 

Mintmark: R thunderbolt Digamma. 

RIC V-2 Rome 157. 

Contributed by Martin Griffiths, 2006.