Notgeld Assistance [resuelto]

Hi, I recently obtained this 10 mark notgeld piece and I'm looking for a little bit of assistance in regards of:
1. where it's from
2. the reasoning for the holes in it.
any assistance would be much appreciated.)

It's from the city of Schleswig like it's written on the note and the holes say it's a specimen "Muster".
Not in the catalog yer though:
https://en.numista.com/catalogue/index.php?e=schleswig_notgeld&r=10+mark&ct=banknote&tbb=y&tbc=y&tbl=y&tbt=y&tbf=y&cat=y&ru=&ca=931&no=&v=&d=&i=&a=&dg=&m=&f=&t=&t2=&u=&g=&se=&c=&wi=&sw=