The absoluteBLACK HOLLOWcage Black is an oversized derailleur pulley cage designed to replace the stock cage on Shimano Dura-Ace 9100/9150/9170 and Ultegra 8000/8050 rear derailleurs. Machined from a carbon-polymer mono-plate and 7075 aluminum, it houses oversized Silicon Nitride ceramic bearings to deliver ultra-quiet operation (12–14 dB noise reduction) and enhanced shifting precision. The asymmetric plate dynamically aligns with chain angle to minimize friction and power loss, while weighing just 71 g. The kit includes the complete cage assembly, lockring tool, and two spare X-ring rubbers.

• Compatibility: Shimano Dura-Ace 9100/9150/9170 and Ultegra 8000/8050 rear derailleurs; fits up to 32 T cassettes; not compatible with Ultegra long-GS cages
• Construction: carbon-polymer mono-plate with 7075 aluminum components
• Bearings: oversized full ceramic (Silicon Nitride balls, Zirconia Oxide races)
• Noise reduction: 12–14 dB quieter than stock pulleys
• Weight: 71 g complete cage
• In the box: complete HOLLOWcage assembly, lockring installation tool, two spare X-ring rubbers