Whether we are servicing our fork or grabbing the part for our local bike shop to service, the Fox Racing Shox Air Shaft Assembly is what we need to change the travel in our 2021 Fox 34 Rhythm forks. This air shaft assembly is available for all Fox Racing Shox Float 34 Rhythm forks variations. The assembly includes the air shaft, negative plate, air piston, crush washer, and pre-installed seals.