They are just starting to appear on MTB rider's heads

but it's worth every cent

A number of gears: 12 speed

AL6061 aluminum Construction balances lightness and strength perfectly

weight-optimized for Enduro

SRAM X-SYNC 12 Speed Chainring - Four Bolt - 107 BCD - Standard Crank Chainline - Oval - 42T - 12 Speed - Blast Black - Alloy Back in Stock They are just starting toSRAM's X Sync Road Chainrings are designed for provide maximum control when used with AXS road cranksets. X SYNC wide tooth, narrow tooth chainring technology provides maximum chain control Laser etched chainring finish is more durable X Range gearing technology gives you more range and a smoother gear progression, so you re always in the right gear Can be installed with a single tool, making gearing changes a breeze Chainring bolts not included