This high-quality EL345 freehub assembly is ideal for replacing the old one in your FSA/Vision Metron rear wheel. It features a SRAM XDR 12 speed drive type, making it suitable as a direct replacement. Genuine Vision spare part. Vision products were launched nearly 20 years ago at the Kona IronMan. Since then they have earned the reputation of being amongst the fastest and most aerodynamic components in the professional field. Vision components are designed using Computational Fluid Dynamics (CFD) software and verified through extensive wind tunnel testing, then proven under its sponsored professional athletes to guarantee you the highest performance.