Rock Shox Reverb Dropper Seatpost  (PRODUCT REF : 500)

Rock Shox new dropper seat post called Reverb really delivers on performance and quality with a total adjustment range around 125mm (4.92in) in infinitely stepless increments, all controlled by a slick push-button hydraulic remote that falls naturally at your thumb and cleanly integrates into Avid's latest brake designs (a separate standalone remote is available for non-Avid users).
Motion of the post is silky smooth, with no notchiness or hesitation – depress the remote plunger and sink your weight onto the saddle and it faithfully drops down each time, every time. Come time to pedal again, hit the plunger again and the Reverb not only springs back to life but does so with tunable return speed thanks to the tool-free adjustable bleed port on the remote.
In addition to being lighter than equivalent cable-actuated remotes, RockShox's hydraulic setup boasts the distinct advantage of being fully sealed, meaning there's virtually no maintenance required after the initial line trimming and rebleed, and no susceptibility to mud or water contamination.
RockShox say the seal design is borrowed from their suspension forks, with triple lips and coil springs wrapped around both top and bottom, and it appears to be working – even dried and tightly caked-on mud is sheared cleanly off, leaving only the slick anodized finish behind. If the seal does get contaminated, RockShox have wisely separated the spring mechanism from the telescoping hardware so even a woefully neglected Reverb isn't likely to leak air or oil. Teardown looks easy to do when eventually needed, too.

Finally, RockShox have even topped the Reverb with an excellent two-bolt head. Saddle installation and position adjustment is straightforward and secure, with outwardly facing bolts that easily accommodate even bulkier tools, and the lower cradle is generously sized for good support of titanium or carbon fiber rails. Weight is also competitive though heavier than claimed at 550g for our 31.6x380mm test sample (it's also available in 30.9 diameter and 420mm length).