Constantine II. AE Follis. Trier. 320-321 AD. 

CONST-ANTINVS IVN NOB C, laureate, draped bust left, holding Victory and mappa.
VIRTVS-EXERCIT, two captives seated at the base of a trophy. 

T-F across fields. 
Mintmark STR. 

RIC VII Trier 289. Very rare (R4).

With permission of Roma Numismatics, Jul, 2010