The Serfas Dual Density line of saddles is constructed using our patented I.C.S. Infinite Comfort System, technology. Made up of a soft flexible rubber base followed by two layers of soft and firm closed cell foam, and a final top layer of friction reducing Reactive Gel covered in moisture-wicking four-way stretch Silk-Tech Lycra. Cutout Base For Soft Tissue Relief, Dual Density Base, Patented I.C.S. System, Deep Groove Design, Rails Steel, Cover Material Silk Tech Lycra. We understand finding the perfect saddle can be tough, which is why every Serfas saddle sold is backed by our 90 Day Comfort and.