I just double checked it with a friends VFC HK416 ... also has those cut outs
The small in the rear tab is: 5mmx4mmx10mm
And the bigger diameter is: 26mm and 20mm deep
I do not have the right tools atm to measure my own PTW upper if they are correct but looking very promising
Original Systema pot metal uppers go for 100$ from HK
RS uppers here in Europe go for about 300-350$ stripped ^^
@Dynamo: .... if it really was a complete PTW upper it should also have the cut out on the underside for the gears so those are not recycled PTW uppers ..... is VFC up to something they haven“t told us about?