the special trick to the 4KS is that a photo from just one side of the key is not enough to make a working key, but the key can still be flipped over and open the lock, even with the 2 sides not being identical
Except one side of the 4ks is enough. Because they're different heights you'd think it would matter. But remember that the key is still reversible, so the sliders are mastered in a way that the same cut on 1 side mirrored to the other will actually still work
There's also a rare variant called the 3KS+ xp, which sometimes has slightly different tracks. I have only seen keys of that though and never a lock. Could that possibly be the lock you have been talking about at the end of the video? Also I am not sure about 3KS+ being able to (reliably) open up 3KS locks. The cut is not only wider on 3KS+ but the first position cut is slightly offset in comparison to the normal 3KS.
Evva has a lot of models with xp in the name, it is the exact same lock just with some dealer crap along with it. It is not the model i was talking about As for the special 3ks+ position, best i can tell it *can* be offset but also can be normal
