Rare Variant U-Boot blc 7x50 Binoculars

[The Devil's Bank]

Can any one identify what model/type/version these blc Binoculars are? (Pictures 1, 2 & 3.)

I believe these to be a very rare variant/prototype.

Serial number:

7x50
61701
blc

Pictures 4 & 5 are of normal blc Bino's without and with the rubbers added.

If you look closely at Picture 4, you will see the two small holes to mount the eye pieces onto the rubber shoulders. (Very top of Bino'.)

See picture 5 with the eye pieces attached.

My blc pair, does not have these holes and the pillar mount is "missing"

[The Devil's Bank]

Now compare the Ocular lenses, you can see the pillar is a different shape..

The variant (Top Picture) is more flat than the rounded pair (bottom Picture).

[The Devil's Bank]

Eye cups can't be added, this pair never had them.

I also tried the rubber shoulders, and they wouldn't fit the variant at all, different size.

Neither would the rubber protectors for the big lenses at the bottom of the glasses??

I sent them to "Optrep" to be cleaned and serviced, as they were in a awful state.

They have have serviced many, many WW2 German Naval Binoculars, but they couldn't identify this particular pair.

The insides had been "messed about with" I was told with small parts missing but now they are fine

So, can any body throw some light onto these blc Binoculars?

I'm baffled and that's not hard