Makita grinder dust shrouds feature a spring-loaded suspension system that keeps the shroud flush to the surface during movement and compensates for blade wear, with soft brushes that help contain the dust and allow for smooth movement over the work surface. After extended use the soft brushes may require replacement, and the Makita Replacement Brush Set installs quickly and easily to help your grinder dust shroud maintain efficient extraction when used with a Makita 7" grinder and vacuum (grinder dust shroud, grinder and vacuum sold separately). Replacement Brush Set model Y-00321 is for use with the Makita 7” Dust Extracting Surface Grinding Shroud (195386-6).