A nice piece.
Coin appreciated by the authors of RIC with a high degree of rarity R3.
Obverse: august's head in a rosette diadem, to the right, in the rim legend:
CONSTAN-TINVS AVG;
Reverse: camp gate of 11 rows of bricks, with open gate, in the rim legend:
PROVIDEN-TIAE AVGG; in section SMANTE;
Bronze, diameter 19 mm, weight 4.08 g, axis 6 h.