Designed to prevent doorknobs from damaging walls, this large concave bumper can also be used as a pad where a larger bearing surface is desired. It is formed of polyurethane with a soft durometer reading; it's a sturdy non-marring material with good skid resistance and vibration-dampening properties. Measuring 46mm in diameter by 16mm thick, it has a high-tack adhesive backing that mounts on virtually any clean, dry, smooth surface.