Cron with two focus knobs?

[Sumo_du_Jour]

Winging it's way down-under from KBCamera, a Cron 35mm pre-asph with a "reverse focus claw", (Fed Ex International count down: day one of five).

I'd like to learn the story behind this feature.
Is it an original Leica option, or a third party add-on?

There's two focus knobs placed at the opposite sides of the ring.

(Did the prerequisite search of the usual Leica haunts, couldn't find a reference to this topic)

 

[rover]

Franken-lens!!!

Never heard of this before.

 

[Sumo_du_Jour]

Sorry, my mistake. It doesn't have two focus knobs - I mistook the hood release lugs for a pair of focus claws. It simply a different style of focus knob.

It's the excitement of anticipation. New purchase, rush of blood to the head and all that. An health issue frequently documented here.