There are a variety of designs on the FEL TEMP banners with religious symbolism, like crosses and chi-rhos. This one is a common example but it has a nice depiction of a staurogram (which means monogram of the cross). It is made by superimposing a Tau (T) on a Rho (P) and is also called a Tau-Rho. The use of this symbol may be a pictographic representation of Jesus crucified.
Constantius II
A.D. 348- 350
22mm 4.9gm
DN CONSTAN-TIVS P F AVG- pearl-diadem, draped, cuirassed, globe in hand.
FEL TEMP REPARATIO- Emperor bare headed and in military dress standing, holding standard with staurogram on banner in his right hand, resting left hand on shield. Two bound captives kneeling to the left before him.
In ex. ANB
RIC VIII Antioch 125