OK investigation tells it's not the correct brake master cylinder.
Ordered a set 20.64mm revision kit for the 405.
Compared it with the original Bendix master.
Also springs are different.
I would not use it as my master cylinder.
It's totaly different.
Is it totaly useless?
No, I used all rubber from the kit to revive the original Bendix.
This investigation leaded me to the fact this rubbers are used on a wide range of cars.
Also found the rubber kit named D1056 from Seinsa.
If you start looking for that number you find several replacements.
Regards Herman