Selle Italia SLR Carbon Fill S1 Carbon Rails BlackLightweight performance Made with a carbon lay up method to create thinner yet stiff rails The handmade padding is applied only where you need it, helping to keep you comfortable Available with or without a Superflow cutout L3 and L1: Wide intertrochanteric distance and high pelvic rotation (Flow and SuperFlow saddles) S3 and S1: Narrow intertrochanteric distance and high pelvic rotation (Flow and SuperFlow saddles) TECH SPECS Model SLR Carbon Fill