This is an interesting gun with no serial number.  I believe it to be a post plant capture assembly.  What is interesting is that all the parts in the gun are Walther except the slide which is Fabrique Nationale and stamped E/140.  There is also the Ml stamped on the underside of the slide at the rear.  The Walther assembled P.38s with a FN slide are quite rare.  This example shows that the slides were still in the plant at war end.  The barrel and the trigger are in the white.  The slide has a very different blue than the frame.  The slide blue is more of a medium blue where the frame is a dark blue.