WARNING: This page is about a different car, the 2009 Mercedes-Benz E550 and 2008 Mercedes-Benz E550. However, it is still accessible from the selected car via links, so may be relevant.
FG 05/Set B
ENGINES 640, 668
Use:
Assembly link for connecting the repair chain with the installed when changing the timing chain.
NOTE:
The assembly links must not be left in the engine.
Fig 1: Identifying Assembly Link (640 589 02 63 00)