The zipp 20239s with its firecrest rim technology offers superb aero performance straight line sprinting stiffness great stability in crosswinds and are ideal for climbing also being lightweight they deliver precise handling on tricky descents and crisp accelerations when the pressure is on also the 202 is built with the latest iteration of their 188 rear hub the v9 along with new spoke lacing pattern for the rear wheel refinements that result in improved stiffness and durability