Help In Identifying Reich Security Stamp

I have a stamp, similar to the one posted here that I found online. Mine has a different no. and is marked 8 Kssl. The one pictured here is the only 1 I can find online. I dont see it in the Scott catalogue I have - 2019 3A. Is there a special book? Can someone help in telling me how to id it and what it is? Tks

This is a "postal money transfer security control stamp"
Not listed in Scott because it's a revenue stamp.

I wonder if these are city abbreviations: maybe Kassel, Dusseldorf, Speyer ?

Hi Nigel.
You're absolutely right about Spy,and probably about Dssd and Kssl too.

so somewhere I saw a list of postal abbreviations online when I was trying to id this. I thin you are right Nigel. I wish I had printed / bookmarked it, now I cant find it!

here is the one I have

Confirmation for Dusseldorf
https://www.hipstamp.com/listing/st...mnh/16450705

That one looks to be cut or something?

On a stock card in a plastic holder.

These are "German Internal Postal Service Security" stamps.

From German Postal Specialist (USA) June 1997, author Rudolf Anders, page 248, "Apparently some time after the great inflation, in 1924, these stamps were issued after the Reichspost incurred some heavy losses when forgers created fake postal money orders and collected on the same. To combat this sort of loss the Reichpost instituted a system of security stamps with special numbers. The post office created the stamps in denominations of 1,000 Mark and up on watermarked paper with security colors and specialized control numbers. The customers were not aware of the fact that these stamps were affixed on the reverse side of the money order and tied by a special cancel." Designs for the various periods vary a bit. Most of the ones I have seen have the embossed eagle and swastika on them.

I have a few of these with various abbreviated city names such as those shown above. Ai various times, I have seen them offered for sale from the various occupied territories of WWII such as Luxembourg, General Government, and Ukraine.

Nice One's ;-)