Rockshox recommends that you replace your dust wipers every 200 riding hours as part of the regular service intervals. This Dust Seal Kit includes two SKF dust wipers and two foam rings, covering each leg of your suspension fork. It comes in 35mm and 32mm versions to cover just about any Rockshox fork. Pick up a Rockshox Dust Seal Installation tool along with it so you can properly install the seals and keep your fork running as fresh as the day you got it.