Gallienus, AE antoninianus. Rome. Sole reign hybrid. 

IMP GALLIENVS AVG, radiate, cuirassed bust right.
PAX AVGG, Pax standing left, holding branch and transverse sceptre. 
V in left field. 

RIC V-1 (S), Rome 341; Dalheim hoard 12082. 

Hybrid with sole reign obverse and joint reign reverse.

Image is from the Dalheim hoard catalog.