Constans AE3.

Obv: FL CONSTANTIS BEA C

Which I expand tentatively as:-
Flavii Constantis Beati Caesaris  ( To (or for) Flavius Constans blessed
Caesar)

... laureate, draped & cuirassed bust right

Rev: / GLORIA EXERCITVS, two soldiers with spears to either side 
       of two standards, ASIS in ex.
 
Contributed by Michael A. Fox