The CN sport-prototype category is managed by the FIA. Its chassis, crashbox and wing are made out of carbon and its bodywork in fibreglass. The engine's capacity is fixed at 3 litres. The sport-prototype benefits from a very attractive weight to power ratio. The type of engine and chassis manufacturer is not limited, but the models need to comply to the regulations of the series that they are entered in. It's the category with the easiest access to endurance racing in terms of costs, driving and operations. The CN are not just reserved for circuits. They are also allowed to take part in hill climbs.