Märklin H0 Anleitung Seite 33

The spacing for the two tower masts can be shortened as follows:
Step 1:
Push the tower masts together so that the holders for the cross span are
sticking out.
Step 2:
Shorten the holders to the desired length (Example: For 3 K tracks the spacing
on the 74131 cross span is shortened by 1.8 cm / 11/16"). When doing this,
leave 5 mm / 3/16" extra for mounting the cross span.
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