DO NOT HOLD ME TO THIS.........I know the WC MK3 has it on, ...I could be totally wrong.....but I think they are already doing it on sub 12 rifles......again, I could be wrong....so check at point of purchase.
Impact MK3 - heard nothing about that one. They added the Power Plenum, that could have been a MK3 - which they did not do. Would need to be something for all versions to be an MK3 Impact.

G