Does not fit model 4020 and 4010.
Solid steel welded construction Universal Saddle Adapter allows rider to use the saddle of their choice! It even can increase the saddle height by 3.5". Over 6' tall? Want more leg extension? Just remove the FitDesk saddle from the post, install the Universal Saddle Adapter/ Extender on the post using the supplied hardware. Be comfortable and get more leg extension while you surf, read, work or game on your FitDesk! Saddle Clamp not included. Please see the 2nd picture listed for measurements.