Info wanted on Rollei lens

[surfdigby]

I have a (black Singaporean) Rolleiflex SL35 with a curious lens. I've never seen anything similar, and with so few markings on it, I'm having no luck finding information on it.








From what I can tell, it's some sort of close up lens. There's no aperture control, and the focus ring is numbered 1 to 8, but with no marking to signify what they are 1 to 8 of.
The lens cap is held on by 4 ball bearings in the lens housing, which retract by means of a lever that doubles as a support for the end of the lens when you set the camera down.
On the mount, it says "Made by Rollei Singapore", and on the top of the barrel is the reference "5203/05". That's all.



I'm also curious of the significance of the dog with a nail through it's nose.

[JanBoettcher]

Hehe,
the "nail" is an endoscope ... does this give any clues?

The camera's "ground glass" schould be rather clear (not "ground") with a cross hair to it.

Best,
Jan