Compatible with all Quad Lock Motorcycle Mounts and Motorcycle Accessories, the Quad Lock Vibration Dampener reduces most of high-frequency vibrations produced by motorcycles.
You need a M5 bolt with a flat head, an M5 nut. And 3 mini vibration-damping balls. (Ex: https://www.flyingtech.co.uk/frames-props-parts-accessories/mini-vibration-damping-ball-65g-0).