This is the Version with the over sized adjustment knob.
Its a zamak razor as can be seen from the head and the raized text under the head. This one is going to have to be treated carefully because there is a bit of zinc rot and plate loss.
The adjustability is the same on all the versions - it has the strong centre spring that pushes the blade against the topcap. There is a slight difference here in that the center button is substantially bigger then the other two versions and because of this, I would believe that this is the last version. The bigger button that presses against the blade would be more in line with the "new" thinner blades.

There are alignment grooves on the topcap and base plate. The lack of lather grooves means that it needs more rinsing than other razors and also once done shaving with it, this one will need to have all the soap residue completely rinsed away.

How does it shave?
Like the other two - Its a very mild shaver on the low settings. Open it up beyond a full turn and it becomes a pretty effecient shaver.