Inner and outer oval chainrings are optimized with smooth shifting in mind Features smooth angled surfaces, (6) upshifting ramps (outer ring), and (12) downshifting points (outer ring) Oval rings help the rider to spin smoother and more efficiently Example: 32t is equivalent to 30t at dead spot and 34t at the power zone Works with 2x chainring systems and does not require any modification to the front derailleur for use Compatibility: SRAM cranks that have (1) hidden chainring bolt (Force22, Red22) Designed in UK, manufactured in Poland