Legendary stiffness & longevity, the 5mm SR4 chainring offers the highest possible stiffness to weight ratio combined with a hard anodised surface treatment for a long lifespan. This version of the SR4 Chainring features a 120mm BCD, specifically designed to retro fit to SRAM double cranks to transform your bike into the popular 1x format. Hard Anodised Renthal use a hard anodising process to increase the longevity of the SR4 chainring. This durable surface finish not only resists wear, but keeps your SR4 ring looking fresh. Chain Compatibility Compatible with all modern 8, 9, 10 & 11 speed chains. The SR4 works solely as a single chainring in combination with a chain guide for the ultimate drivetrain efficiency. SR4 120mm Specific This SR4 Chainring has an offset tooth bed for enhanced chainline when converting from a double to single set up. The chainring is also treaded to accept standard SRAM hardware. CNC Machined Each SR4 chainring is fully machined from high grade 7075 T6 aluminium. This computer aided design allows Renthal to cut away all un-necessary material to retain an incredible strength to weight ratio. Description by Mark, Rutland Cycling Web Team.