Hans Grohe Raindance Connect Showerpipe 27164001 Installation Instructions / Warranty page 6

Install the showerhead on the shower arm.
Use a level to make sure that the shower arm is straight.
If it is not, loosen the mounting screws slightly with an 8
mm wrench. Reposition the arm until it is straight. Tighten
the mounting screws.
Attach the escutcheons to the flanges by rotating them
clockwise.
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