OSPW Aero ALPHA, Shimano 9250/8150, Black

- Updates the fastest proven aero derailleur cage to include patent pending ADR bearing protection and quiet performing ALPHA disc with composite tooth profile pulleys\n- Pinstripe graphic has been added for a splash of visual motion\n- OSPW Aero ALPHA cages have been updated to accommodate the ADR equipped ALPHA disc pulleys\n- Reduces aerodynamic drag on the rear derailleur by up to 60%\n- Reduces friction by 35-40% over stock pulley configuration\n- Structural aerodynamic cage design\n- Pulleys, cages, and bearings all produced and assembled by hand in Denmark\n- ALPHA Disc pulleys with composite teeth for quiet performance and ADR bearing protection\n- It is not possible to add these pulleys to a previous generation OSPW Aero cage