- XTR M9100 Series CS-M9100-12 12-speed cassette- Average weight: 357g (10-45T), 367g (10-51T)Combinations: - 10 – 45T: 10-12-14-16-18-21-24-28-32-36-40-45T- 10 – 51T: 10-12-14-16-18-21-24-28-33-39-45-51T