Swix Racing Roto Horsehair XC 70 mm - The Racing Roto Horsehair Cross Country 70mm brush is part of the Swix series of XC brushes in 70mm, allowing you to combine the brushes that best suit your purpose. Using the horsehair brush is the second step in polishing the base after applying liquids and hot waxes. First you use a steel brush, then the horsehair brush and finally the nylon brush. Attach two 70mm brushes to the 140mm Roto cover handle. Then attach the Roto Cover with the brushes to your drill. Because you are attaching a 70mm brush to a 140mm Roto Cover handle, you can easily combine brushes on the Roto Cover handle. A nylon brush and a horsehair brush. For best results, we recommend using a drill with a minimum speed of 1800 rpm.