Brooks england cambium c13 saddlethe cambium c13 is made from a vulcanised natural rubber top that follows the movements of the rider for responsive control and all day comfort suspended over a one piece braided carbon frame the c13 weighs150g less than the popular c15 model as with their other cambium models prior to their release brooks provided hundreds of c13 saddles to testers around the world they take this step to ensure comprehensive real world feedback from professional cyclists t