How to ID ww1 shoulder titles

[kpl1]

Hello

How can I see the differences between a ww2 and a ww1 metal shoulder title? I'have seen some titles wearuing a maker at the back. some are Gaunt London marked, some from canadian manufacturers. I know there are a lot of different titles but is there a general point (type of lugs for instance) that is typical for one period?

Hope someone can help me with this.

Kind regards,