Burda RELAX GLASS SOUND Montage- Und Gebrauchsanweisung Seite 10

5. Install two brackets on the ceiling or wall with the following minimum recommended bracket
distance "B".
"B"
MIN. DISTANCE (mm)
500 ±50
6. Set the adjustable angle mounting brackets to desired angle and fasten brackets by spanner
For ceiling mounted installation, the available mount angles are restricted to 0°, 15° and 30° only.
For wall mounted installation, the available mount angles are restricted to 15°, 30° and 45° only.
7. Hang the device on the brackets and firmly secure in place with the mounting bracket locking plates
by tightening bolts labelled A.
Recommendation: Switch on the device using the switch on the back before you install it