The Butterfly Carbon is the lightest of the Butterflies thanks to the addition of carbon rails. It's wider in the rear than typical saddles for good support of a woman's sit bones. The Butterfly Carbon's low profile, flat top and a complete cutaway through the center are designed to provide pressure relief and support in the right areas. Injection-molded foam is used to provide the right balance of softness and stiffness so you won't sink into the saddle the longer you ride.