[stephen f. polyak]

Matt,

I suggest that "4250" relates to this cooler flap assembly, and not the particular airplane the assembly was installed on. Plates of this type marked various assemblies and parts on an aircraft. Normally, the applied Werk.-Nr. was used to record fabrication of the assembly/part (in this case, part number "109.581-003 G") unit. The airframe werk number (for the aircraft the assembly was later used on) was unrelated to the assembly number.

That said, plates like this did sometimes list the airframe werk number. However, in those cases the Sach-Nr entry line normally listed the airplane model (e.g., Me 109 G6).

Steve