I'm aware of the 20-60x85 old version and the new 27-60x85 version which this one is. As far as generations of the new version I'm not sure what you'd be referring to.Is this the gen 1 or gen 2 version?
This would be the gen2 I believe the older less powerful was gen 1 then they made the “upgrades” to this one.Sorry, while researching this I found an ad for one that claimed to be Gen2, just trying to better understand the specifics.