Serfas RX Saddles are designed to increase blood flow and alleviate numbness Serfas RX designed saddles have a full length anatomical groove down the middle of the saddle along with an elevated seat position. This has proven to eliminate pressure and significantly reduce numbness around your soft tissue (plumbing) and put weight where it belongsaround your sit bones. This means you can spend more time in the saddle without sacrificing comfort.Dual Density Base with newTwin Bar DesignPatented ICS Comfort SystemBest protection against numbnessSteel Rails, Weighs 485 gramsWaterproof, Breathable Microfiber Cover234mm X 178mm