Kerryman,
I guess all fore end hooks are imbedded into fore end...and since the Darne shown has no detachable fore end and only one hook (the bbl hook)...It looks like PBT's interpretation is correct...but...I still don't see any dovetails on the lower grade guns marked crochet encastre...
That's great info about the Velcro...it reminds me of story I heard in college about a couple of chemical engineers who worked for Westinghouse Electric...they were trying to come up with a non-conductive substitute to replace the material being used at the time as an insulator, mica...originally it was a substitute for mica...hense the name Formica
Jim,
I'm sort of a beginner on Manufrance....that's the first time I've noticed a Robust to have the barrel lump completely through the bottom of the receiver. This Robust does not.

Also, I have speculated that this may be the year of manufacture...but again, I don't really know...does your Robust have a similar markings under the top lever?
If you compare this photo with the fore end iron photo above, you can clearly see the extra "22" has nothing to do with the serial number.
and lastly...your photography is so much better than mine..do you have any advice on what I'm doing wrong?