The 123\CITROËN-DV-4-R-V (also known as 123\DV-R-V) is essentially the same unit as the 123\DS-A-V or the 123\DS-R-V : it contains the same set of 16 advance-curves.
Might you require a non-vacuum-advance: specify a ‘123\CITROËN-DV-4-R’.
The difference is its shape to fit certain “DV” engines, as Citroën produced in 1966 and 1967. This can easily be seen, by the two M7 – bolts sticking out of the engine, for mounting the distributor. This explains the different shape of this 123-ignition.