Just to let you know the ANVIS system is made by ITT and Northrop Grumman, both are the same, identical except the sticker. ANVIS 9 and ANVIS 6 differ slightly but 9 is the latest, which most people use if they do not want to use a HUD on the end.
As for what tubes are in them, in Europe there is one company already assembling DEP tubes into the ANVIS shells under licence, this is where it gets technical but in essence you still need a licence to buy them but they are in fact better than the US models on offer because of the export rules imposed by uncle sam.
ANVIS 7 are for people driving 4x4s, beware of offers that are cheap, usually there is a non-aviation tube in there (commercial grade) which is cheap but full of blemishes etc.
Expect to pay around €14k for a set of European tubed ANVIS 6 or 9, but they are much better than the restricted performance US ones at around €11K.
Send me an email and I’ll bore the t*ts off you on NVG in general! I will ask my supplier (of NVG not weed) to get on this forum and maybe he will shed some more light on the subject.
This is me:
[email protected] hope it helps
SF