AbsoluteBlack Hollowcage V2 Carbon Ceramic Oversized Derailleur Pulley Cage - Shimano Dura-Ace R9250

The AbsoluteBlack HOLLOWcage V2 replaces the stock derailleur cage on a Shimano Dura-Ace R9250 groupset with a single-plate carbon-polymer design built specifically for 12-speed Di2. AbsoluteBlack molds the mono-plate from the same carbon-polymer matrix SRAM uses in its RED eTap AXS cage, and this V2 version carries a glossy finish that shows off the carbon weave rather than hiding it under a matte coat.

The cage runs on full ceramic bearings that AbsoluteBlack had independently certified through X-ray diffraction testing at Lucideon, a UKAS-accredited materials lab — a level of verification most oversized pulley brands don't bother with. Paired with the bearings is AbsoluteBlack's trademarked Xring Pulley, engineered specifically to cut down on the chain noise that oversized cages can sometimes amplify rather than reduce. At 66 grams, the complete cage is light enough that the swap barely registers on the scale, and it's built to work with cassettes up to 34T, which covers the range most Dura-Ace riders are already running.

Fit is specific: this cage is designed for Shimano Dura-Ace 9200 and 9250 12-speed derailleurs only, and installation is straightforward with the included lockring tool. AbsoluteBlack backs the cage with a 12-month warranty and offers it in five finishes — Black, Titanium, Gold, Red, and PVD Rainbow — so it's as much a styling upgrade as a mechanical one for a rider looking to dress up a top-tier Shimano build.