BXI - Anti Vibration Isolation Pads - Composed of Rubber & Cork - Thick & Heavy - Excellent at Low Frequencies, Great Acoustic Isolation for Speakers, Washers, Machines, etc (2'' X 2'' X 2'', 4 Pack)

See the headline. I don't think the pictures really do them justice, when I opened the box I was taken by surprise by the mottled colors and texture. They look like kind of gross sesame tofu cubes or something, and they smell very plastic-foamy. That said, how often are you going to put your nose up close to them? All I know is I haven't had any complaints from the downstairs neighbors and the subwoofer rests on top of them just fine.

These isolate vibrations making your sub sharper and deeper, but, I accomplished the same thing using a cut out piece of foam insulation which is way more stable and easier to pick up.

Quality is just ok, the faces of the cube aren't even. Some faces have clear saw marks and lines on them and the material crumbles apart super easily.They seem to work for now, though the size is not uniform between the four blocks. They don't seem like they will last very long.

Literally falling apart in the package not even cubes, look like they were hand cut from a large piece with a dull knife.

The glue that holds the cork and rubber bits together is not very good. Just holding the blocks caused pieces to fall off. The blocks arrived as different sizes and not fully cut through leaving little bits on the end. I had to cut off the remains with scissors.Thankfully, two blocks where the same size while the other two were also the same size. If they were odd sizes that would induce wobble in my 3D printer. Despite these product defects, they do their job. I would only use these indoors and away from moisture.If it weren't for these obvious production defects I would give these 5 stars.