In the two extreme corners of the rear wall there is a niche in which a metal bar or rail disappears. This ‘upper rail’ to the construction of the cockpit. The rail is on the bottom open and would serve as a conductor of window P2 (not official source).

The housing at the front around the rail is in the real out of foam rubber. My copies are of mdf-strips are used. Mdf is also easy to edit.

Against the housing, there is also a black tube that is towards the front of the cockpit. The function of this is unknown to me.

Additional information and images can be found on following link: https://www.flightdeck737.be/hardware/platform/aft-flight-deck/onderdelen-achterwand-fo-zijde/upper-rail-window-p2/

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