heavy cavalry engaging heavy cavalry

[Flavivs Aetivs]

I know the Persians adopted Cataphracts, but I don't know when (some time during the Achameanids though). the First Roman use of Catafractarii is recorded under the Emperor Hadrian in 130-something AD on a Tombstone in the middle east (Syria, I think, but I don't know). They became prevalent after the rise of the Sassanids in the 210's and 220's as the Army adapted to fight their new enemy, which was more organized and stable than the earlier Parthians.