A wheel lock pistol by Valentin Klett the Younger

[Ole S]

I recently acquired the wheel lock pistol shown in the photos. On the barrel, and on the inside of the lock it has the mark of Valentin Klett the Younger, Suhl (1567-1630) Støckel number 592. Total length 66 cm, barrel length 44,5 cm, caliber 15,5 mm. Weight 1614 g. When the lock is taken out, it becomes clear that some signs are incised in the stock (see photo).
According to Støckel, the stockmakers in Suhl were required to sign with a "Zeichen", but I have not been able to find any information about this.
Can anyone help me out here?
Ole