One dropped chain is one too many. The perfect companion for single-chainring setups, the 1x SL strikes the perfect balance between lightweight construction and durability, ensuring long-lasting performance without adding unnecessary weight to your bike. With its user-friendly design and straightforward installation process, setting up the 1x is quick and hassle-free.Works ONLY with MY21+ Trek Procaliber and Supercaliber, MY20-21 Trek Top FuelClamps around BB92 bottom bracket shellAluminum backplate is strong and lightweightWorks with 30-36t round rings (and 28-34t oval rings)Works with 52-55mm chainlines with spacer-free chainline adjustment so adjustments can be made quicklyForefront 4-way, front-accessible setup and adjustmentPop-Up tool-free chain access for simplified installation and drivetrain maintenanceItem SpecificationsChainguide Mount TypeBB Cup MountColorBlackDefined ColorBlackMaterialAluminumMaterialCompositeMax Tooth (teeth)36 MRP 1x SL Chainguide Chain Retention System UPC: 702430208277