WARNING: This page is about a different car, the 2009 Mercedes-Benz CLK350 and 2008 Mercedes-Benz CLK350. However, it is still accessible from the selected car via links, so may be relevant.
FG 00
MODEL 107, 114, 115, 116, 123
Use/specification:
Support block (1-piece) for jacking-up and lifting
Fig 1: Identifying Support Block (123 589 11 63 00)