absoluteBLACK are premium oval chainrings designed in the UK and manufactured in Poland from German materials. Independent studies led by the University of Primorska, Slovenia show significant differences when using absoluteBLACK Oval chainrings compared to round. Up to 9% increase of Force effectiveness, up to 7% less oxygen consumption, up to 15% less Ventilation (breathing) and up to 10% heart rate decrease when using oval chainrings versus round.