Shimano Oversized Derailleur Cage - Dura Ace R9100 and Ultegra R8000 - Black
Kolossos is the Greek word for a statue, much larger than the original subject. Seems fitting for an oversized derailleur cage.
Imagine the performance of replacing your stock pulleys with a ceramic 12-tooth top pulley and a 19-tooth bottom pulley built on the stiffest cage on the market.
Besides reduced friction, this cage is built with shifting accuracy, gravel worthiness and chain retention in mind.
This model will fit on Dura Ace R9100 and Ultegra R8000 series derailleurs. This includes mechanical and Di2 as well as short (SS) and medium (GS) cage lengths.
Please note** Installing this oversized derailleur cage typically requires replacing your chain to accommodate the larger pulleys.