Suspicious s/42 on WW1 DWM

[kubel]

The Germans did the same thing when they upgraded the WWI-era Gewehr 98 rifles to WWII standards. I have a 1916 Gewehr 98 that was reissued for WWII use and it's marked "S/42" on the right side of the receiver and the rear sight parts. I would assume they did the same thing to pre-WWII pistols that were intended to be used by the Wehrmacht.