The Walther P4 is an improved version of the venerable Walther P38 introduced in the late 1970s. The P38 was originally developed as the service pistol of the Wehrmacht at the beginning of World War II, and versions of it remained in service with military and police forces worldwide up until the apocalypse. While largely displaced in Morrow Project armories by the Glock 26, the P4 was issued to some of the first Morrow Project teams buried, and remained an option for team members throughout the entirety of the Morrow Project.
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