Any idea on this and what would have fired it please

[simonb]

Hi all. New to this forum. I found this whilst metal detecting at the weekend and wondered if anyone could ID it for me and who and what would have fired it. It has No 208 and 1942 at the end of a series of numbers that I can't quite make out Thankyou

 

[Alpini]

Then it's the damaged part of a No. 208 mechanical time fuze.

 

[SG500]

Worth checking this out.
Dave