The SPARE - REAR DERAILLEUR PULLEY AND INNER CAGE GX EAGLE X-SYNC: BLACK from SRAM Sram Manufacturer Specific. Available in BLACK and NO SIZE. See the entire range of SRAM products available at The Bike Factory here. A really good value, technically advanced item selected by our buyers to give our customers quality where every item is conceptualised and designed to complement one another and function together allowing year-round healthy cycling.