SILENCE, ACTION. THE NEW CHORUS 11-SPEED CHAIN IS QUIETER THAN EVER. The new 5.5 millimetre thickness has been combined with new materials and a special anti-friction treatment which permits outstanding fluidity. We have reduced the width of the chain to 5.5 millimetres with the new spacing and a new material has been envisaged for the outer links. The pins are hollow inside to reduce the weight while maintaining strength. It is necessary to use tool UT-CN300 to fit it. The Ni-PTFE treatment ensures smoothness and long life. The Ultra-Link fastening system guarantees strength and operation with the new 11-speed sprockets. HD-Link extremely high retention force lightened links weight savings antifriction treatment smoothness, long life width 5.9mm quiet operation, less interference with adjacent sprockets and chainrings high-performance shifting