SRAM X-Sync Pulley Assembly, Fits X01, X01DH, X1, GX 1x11, NX, Force CX1, Force 1, Rival 1, Apex 1 Derailleurs. MPN: 11.7518.032.000 - SRAM - Pulley Assemblies - Pulley Assembly. Wide-narrow pulley tooth profile holds the chain better.
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