[eclam]

The factory offers 2 different sights other than the
one shipped with the gun. "drift adjustable" and "tritium".

Are either of these "fixed" in the traditional fixed sense?
(adjustment only by using a punch and hammer to drift
them back and forth)?

 

[M700Police]

From the picture and description posted on the Walther international website, it appears that the "drift adjustable" sight is the same as the one that comes on the gun but metal.

http://www.carl-walther.de/englisch/defense/defense-40.html