Oversized pulley system for Shimano 10/11v Dura-Ace and Ultegra derailleurs.

With 2 sheaves of 14+16 specific narrow-wide teeth with ceramic bearings.

Offers savings in transmission friction.

Compatible with the following changes:

Shimano Dura-Ace 10 speed RD-7900-SS

Shimano Dura-Ace Di2 10s RD-7970-SS

Shimano Dura-Ace 11s RD-9000-SS

Shimano Ultegra Di2 10v RD-6770-SS

Shimano Ultegra 11s RD-6800-SS

Shimano Ultegra Di2 11s RD-6870-SS