Constantine I, AE follis, Siscia. 

CONSTA-NTINVS AVG, helmeted, cuirassed bust right.
VICT dot LAETAE PRINC PERP, two Victories standing facing 
each other, holding shield inscribed VOT PR on an altar decorated with the letter S (Helvetica 6f). 

Mintmark Gamma SIS dot. 

Bikic-Do hoard, Sirmium VIII Siscia, 388; RIC VII 102 var (obv. legend).