Stempel-Schulz commemorative plaque, age?

Wall plaque commemorating 100 years of water service and 125 years of gas service South Hessian gas and water. Frone had Darmstadt City with their coat of arms.
I'm not finding anything on South hessian G & W and when this might have been done for them.
There is also very few item made by this company Stempel-Schulz that i can find online. I know they have been in business since the late 1800's. Plaque is 4 1/2" diameter. Also needs a hanger which i haven't been able to locate anywhere.

Mikey

 

Here it is complete.

Debora

 

Company appears to have changed its name.

https://de.wikipedia.org/wiki/Entega

Debora

 

Where did you find that?

 

Via the worldwide web. Google Germany (google.de.)

Debora

 

Thanks Debora, looks like this dates to the 1970s.

Mike

 

HI Mike,
I kept thinking where have I seen that before. Then when I walking out into the hallway I espied this hanging medal. Mine is Mary's Church in Gelnhausen Germany.
I think that it has the same hangers.
greg