Here the boards of Feldartillerie Regiment 12 and 32 side by Side. Also two tunics. One from the regular Feldartillerie Regiment 12 and one from the Reitende Abteilung Feldartillerie Regiment 12. The difference is good to see.
I'd be happy to try. But the leather strap is still closed in its original form and I don't want to change anything. Inside is gray coarse fabric with the stamped size 57