Shimano XTR CS-M9100-12 Cassette Lock Ring and Spacer Description: This Shimano XTR CS-M9100-12 Cassette Lock Ring and Spacer works to replace or repair Cassette Lock Rings and Spacers found onboard Shimano XTR CS-M9100-12 Cassettes, along with select other cassettes. Features: Replacement Cassette Lock Rings and Spacers for Shimano XTR CS-M9100-12 12-speed Cassettes See compatibility tab for full list of compatible cassettes Specifications: Material: Alloy Color: Black