They are designed to insert the strip along the entire edge of the frame. The light will be emitted at 90 degrees, towards the sides of the frame.
Each piece installs with a single screw or double-layer adhesive.
Depending on the frame, 4 corners and at least one straight piece will be needed to fix the start and end of the LED strip. I usually install 4-5 straight pieces, avoiding the strip from curving between corners.
The initial design is for a 4mm COB strip. The greater the width, the more difficult it will be for the frame to be close to the wall.
Even so, I will also leave designs for 2.7mm, 8mm and 10mm LED strips