Serfas TailbonesA(R) saddles supports the sit bones and provides a smooth comfortable ride using Progressive Density Foam while a Deep Groove Design allows maximum blood flow into the neurovascular bundle for drastically reduced numbness and discomfort.Our latest addition to the TailbonesA(R) family introduces a top layer of Memory Foam for a more personalized feel as well as added comfort. Lycra Cover Specs: Length: 271mm / 10.6" Width: 272mm / 10.7" Weight: 1,112g+/- Vinyl Cover Specs: Length: 271mm / 10.66" Width: 271mm / 10.66" Weight: 999g+/- Features: Elastomer Suspension Top Layer of Memory Foam For Added Comfort High Sit Area For Soft Tissue Relief Progressive Foam Technology Relaxed Riding Position Rails: Steel Cover: Four-Way Stretch LycraA(R) or Waterproof Vinyl