This door knob wall protector is crafted from soft rubber and 3M strong self adhesive glue. It protects the door, wall, baby from collision. Idea for household, stick on door knob, desk and table, chair, toilet, the bottom of electrical, speaker. Reduce the shock noise, protect your home furniture from damage and noises. Size: diameter: 1. 97inch (5cm), thickness: 0. 4inch (1cm).