1906 Navy with " I.S.B."-question

[Jamka]

Matthias,

Guten Tag -
In Jan C. Still's book "Imperial Lugers", on pages 195/196 is stated:
Navy Variation 1906, Marked I.S.B. SN# 76 - 702, 8 reported.
This was the state of reported numbers in 1988.
Yours would certainly add to this number.

B.T.W., I have a same model, #3036a, matching mag, marked on the rear with III.St.S.B. 22.
That reads "Drittes Stamm Seebatalion"... In Still's book none were reported at the time.
This Luger stayed in Cuxhaven for the personnel and training unit.

Good Luck !