The Expander No. 2 is engineered specifically for BMC carbon steerer forks. Measuring 50 mm in length with a Ø23.4 mm outer diameter, it is designed to fit steerer tubes with an internal diameter of Ø23.3–24 mm, ensuring a precise and secure interface. The set includes a compression bolt and is compatible with standard top caps. By providing consistent compression forces and reliable headset preload, the Expander No. 2 supports secure headset installation while helping protect the integrity of the carbon steerer structure.