STRONGLIGHT chain ring ´´CT2´´ Mod.19 4-arm, for 11-speed, 110mm circle diameter, aluminium 7075 T6, black self-service package, with CT2, ceramic-teflon coating, compatible with Shimano Ultegra FC-R8000 and FC-R8050, weight:145g (outside, 55 teeth), 40g (inside, 34 teeth).SPECIFICATIONS:-52 teeth, outside (only combinable with 38 teeth chain ring).