The SRAM OG 1090 cassette is both elegant and efficient, and delivers high performance. Savor its titanium-like weight and solid steel strength and stiffness. Produced in limited production runs, SRAM Red components are crafted around 3 key concepts: advanced materials, light weight and premium efficiency. Main cogset is machined from a single forged form that is heat treated and then shaped in a complex series of CNC-guided operations. Sprockets (including 2 free cogs) are designed using SRAM proprietary