Designed for use with Sram`s new RED XPLR AXS power meter, these replacement rings are purpose made for use with Thread Mount spider designsMount system allows minimization of weight, maximum stiffness and accuracy, and retains the ability to swap ring sizesSRAM Threaded chainring removal tool required for installationAvailable in 38T, 40T, 42T, 44T, and 46TCompatible with all Flattop chainsThread Mount42TAluminumBlack/SilverFlattopNarrow/WideUPC/EAN/GTIN: 710845899614