From the company that loves speed comes an 'unstiff' seatpost that will smooth your world. Niner's RDO carbon seatpost is designed to deflect more than other carbon posts, offering a small degree of suspension that makes a big difference by the end of your ride, whether you rock a rigid singlespeed or a full-suspension.
This is really one of the best carbon seat post expecially for a rigid bike. I ride a rigid ss and the RDO carbon gives you a flex that gives you the extra cushion you need on a rigid bike. A+ in my book