No 17 Question

[Weasel]

Hi All,
I came across this number 17 German bomb fuze a few days ago at a display but could not get any info on it from the man at the table.
These are not my area of expertise at all so i am really interested in finding out from one of you fuze collectors out there what the black rubber ring is around the base of this one ?
Best regards Weasel.

 

[Madbomber31]

Just need the clock and the rubber around it :bigsmile:
Its to keep the water out of the clock work.