Attaching them can be a trial and error thing, I ended up using double stick tape on all four sides and that seems to work fine and doesn't damage the wall.

Hard plaster walls and needed something to stop sound bouncing all over.

But they make great wall decorations.

It's a great wall decoration, but if you are looking for something to really help with acoustics plz don't go with this

I decided on these because my walls were super empty and they work perfect for my red and black setup.

The foam has helped to absorb sound & protect the wall.

i want to at any time and not destroy my walls

Perfect, great Wall art that helps my neighbors out, the color is great

Their easy to mount on the walls with a single tpin in the middle or spray glue, there are many kinds & brands but fabric glue spray is pretty strong stuff, just be careful not to damage your wall or the foam as they might not come off so easily

They do what they are supposed to do, and double as a cool looking wall piece depending on how you organize them.

Two way sticky tabs work well for attaching to wall.

Two way sticky tabs work well for attaching to wall.

Using thumbtacks, I placed these around my computers as well as on the wall behind my couch to hopefully make a difference