SRAM X-Sync Steel Direct Mount Chainring 28T Boost 3mm OffsetSRAM X Sync Steel Direct Mount Chainring 28T Boost 3mm Offset. The SRAM X SYNC STEEL 1x chainrings are the perfect replacement ring for the cost conscious with added durability of steel. The same SRAM X SYNC technology at a lower price. Compatible with all SRAM 1x cranks TECH SPECS Tooth Count 28 Round or Oval Round Drivetrain Speeds 10 Drivetrain Speeds 11 Direct Mount Type Direct Mount SRAM Defined Color Black Ring Position Type Chain Retaining