One of the Attwood .pdf docs for these Centric II seats lists a suspension option:
"The SAS suspension is an option for the more advanced applications, where maximum comfort and support is desired".
Their drawings are pretty cryptic, but it appears that the seat cushion sits over tensioned cables, each individually connecting to a spring.
I'm familiar with other marine/truck seat suspension systems, and this one seems to be pretty minimalist, and totally concealed withing the seat itself.
Some seat suspension systems are larger than the seat itself, and have a combo of springs and hydraulic shock absorbers, with multiple adjustments, so I'm not expecting a lot from Attwood's solution.
Attwood is impressive in that virtually every component of their seats is available as a repair part, something totally lacking with many other marine seat brands...could make the difference between fixing and replacing sometime down the road.
Any experience with these?