Air shafts for Marzocchi Super Z and Bomber Z forks. Simply purchase the air shaft in the travel that you want your fork to be and install it into your fork to change the travel. Choose from 150mm, 160mm, 170mm, 180mm, or 190mm. Includes brand new seals pre-installed and a new crush washer. Compatible with 38mm stanchion single crown Marzocchi forks (Super Z and Bomber Z). Reassemble the fork with Fox 20wt Gold Oil, Fox 4wt Damper Oil and Slickoleum. Reference our Oil Volumes Database for proper oil volume.