Holder for the idle (or progression) jet for the Weber DCNF series carburetor.
This is the now obsolete version of this idle jet holder that measures some 17 mm in overall length.
Later versions of these carburetors used a different version holder that measured 13 mm in overall length.
That new version can be found HERE.
The production of these old version was stopped by Weber many years ago and consequently, these are so-called New-Old-Stock jet holders and they are only available as long as the stock lasts!
Required quantity per carburettor: 2
This is item number 27 in the drawing.