Flat Disc Wafer Brush is installed on front mounted sweeper for snow sweeping or road sweeping. The peak season for this brush is when winter is coming. There are pins inside the metal or plastic channel. During installation, we need put and assemble these wafer accoridng to the position of pin. You can also google " how to install wafer brush" or us. We have full range bristle material, which is the most important factor for its performance.