Wonder if I could ask some advice guys,on this EK1. It is maker marked KO & is vaulted. I can't see any differences between this & other EK1s on the forum, the font seems the same & the crown seems to conform too. The pin assembly looks correct, maybe the 'pin' is a bit shorter than others I have seen & the EK is vaulted, would this be a problem (should a KO marked EK1 be flat ?) at all ? Is it possible to determine if this EK is 1914-18 manufactured & not post WW1 ?