7075-T6 aluminum, hard anodized finish with PowerGlide ramps/pins for optimized shifting performance (newer black rings can be used to replace older tungsten grey rings of same BCD and arm/spider profile)
- For SRAM Red, Force, Rival, Apex, S900/950, S500/550, S150, and Quarq-CinQo crank models *(not for 2012 'New-Red'' cranks with hidden-bolt spider)