Product Description - prevents noise The spacer for the Shimano XTR CS-M9100-12 cassette is a thin spacer that prevents potential noise development. As a so-called low spacer, it is mounted between the spider arm and the freehub body. Shimano has included it with all CS-M9100-12 cassettes since the end of 2018. It is not necessary for the XT and SLX 12-speed cassettes, as these, like the XTR successor model CS-M9101-12, are equipped with a pre-installed adhesive ring. Product Specifications: Application: MTB, Cross Country Compatibility: XTR CS-M9100-12 Product Features: Spacer for Shimano XTR CS-M9100-12 to reduce noise Reduces noise development Thin washer placed between spider arm and freehub body Manufacturer Number: universal: Y1X401500 Contents: 1 x Shimano spacer Manufacturer: Shimano Europe B.V. High Tech Campus 92 5656 AG Eindhoven Netherlands info@shimano-eu.com