SRAM RED 2x Chainring Kit - 50/37t, 2x12-Speed, 8-Bolt Direct Mount, Black/Silver, E1SRAM's lightest, stiffest, and most durable chainring. Their one piece construction ensures that none of your effort goes to waste. A 13 tooth delta on all chainring pairs ensures precise shifting for any setup, as well as a less dramatic change in cadence during front shifts. And the technology packed in makes this SRAM longest lasting chainring set ever. Crisp and accurate front shifts One piece construction for faster, smoother, more secure