That was my confusion and if your comment is accurate, then that's cleared up (though a full list would be great, for example, we assume the AD uses the same filter too and it's not in those 2 main series). But the thing to note even in your own comment is that you say the "Phantom and Sagaris" models use the same filters. The Air
IS a Phantom model, it's officially the Phantom Air. So a definition of what can go with was clearly set out by
@Bobtrinity
would be best, as both you and I can only be so accurate with speculation