

Hello,
Recently aquired this interesting little Steel gauge relating to the 9.2" HE shell.
Stamped into it is: (from top to bottom)
2.249
9.2" HE. HOW SHELL. MK2 . 3X
LENGTH OF SCREW
5 (in oval circle) S. 3-16
W&S OTLEY. NSF LEEDS
2.211
My questions are: Length of screw? What part of the shell does this relate to? Fuze socket?
What does the 'X' after the 3 indicate?
The 5 in circle and 'S'? Is this a gauge type ID stamp?
Finally, any history or background on W & S Otley?
I know its a lot to ask. I'd really appreciate any information so I can understand more about this interesting little piece.
Many thanks in advance!