Use the Swix Rectangular Stiff Nylon Brush as the first brush on fluorocarbon ski waxes. This unique brush has the ability to help brush up the fluorocarbons in Cera F powder overlays, so your ski glides efficiently and quickly over the snow. Professional ski tuners and racers love this specialized ski brush for advanced tuning. It is recommended to only use it on fluorinated waxes. If you choose to use it on other waxes, use a different rectangular brush for each chemical makeup of wax.