Step 3: Place the sound-absorbing panels in the frame
Before inserting the acoustic panel into the frame, screw the white mounting pieces into the frame. When the mounting pieces are firmly screwed into the frame, you can attach the acoustic panel (with the hard side facing the wall) to the panel.
Stick the supplied corners (with a Velcro and adhesive side) on the wall, behind the soundproof panels. This keeps the panel extra well in place.