Serfas RX-921L Road/MTB Comfort RX Saddle - Men's 90-Day Comfort Guarantee on all saddles Patented I.C.S. Infinite Comfort System RX & Deep Groove designs Dual Density base technology Patented Dual Density Base ICS Technology for supported comfort RX Cut out eliminates all numbness associated with prolonged cycling Available in Lycra or waterproof microfiber cover