Shimano GRX and Ultegra RX800 Oversized Derailleur Cage - Black
Kolossos is the Greek word for a statue, much larger than the original subject. Seems fitting for an oversized derailleur cage with a 19 tooth bottom wheel.
Besides reduced friction, this cage is built with shifting accuracy and chain retention in mind. Kogel Bearings has always had a strong connection to off-road disciplines. We wouldn't build it if it weren't gravel proof.
Oversized pulley systems are an excellent way of reducing the additional friction caused by clutch derailleurs.
This model is built for the GRX 2X (RD-RX810) and Ultegra RX800 series derailleurs. This includes mechanical and Di2.
This cage fits on the GRX 1x derailleur (RD-RX812) and will allow to shift through the entire range on an 11-42 cassette, but it will leave a large spacing between the top pulley and the smaller cogs. Expect shifting to be less snappy in these three gears in a 1x setup.