Tool makers mark ID.

[Swingpress]

I am having trouble identifying this mark. On a set of pliers and it is the only mark I can find. I am hoping someone will recognize right off the bat and I'll probably feel silly. Big thanks to whoever can help!

 

[twertsy]

I haven't come across that one yet but I'm only up to 1890. Those look a bit more modern.

 

[Advan]

Those look a lot like these Klein 9" linesman's...

 

[Advan]

http://alloy-artifacts.org/klein-tools.html#trademarks


I just found some more info, where E-EN would mean a manufacturing date of April 1946, according to Klein's nomenclature. Not sure what the Delta means.