•The heavy duty driver tube and specially-sized aluminum setting rings can safely, quickly and precisely install crown races.
TB-1938: includes 6 rings for most 1" and 1-1/8" headset systems.
TB-1939: includes 2 rings for 1.5" and 1-1/4" headset systems.
Super B/TB-1938&1939 Crown race setting system(EN)
Super B/TB-1938&1939 Crown race setting system(中文)