Deity Revolution Sprocket Featuring full countersunk hardware and machined from 7075 T6 aluminum . The Revolution series is not your average sprocket! Design for 8/9 speed chains. Accepts Direct Mount of any 4B on the market, and simplifies set up with all chainguides,The Revolution Series replaces your standard spider + Chainring combo into one single unit! Whether you are on the race circuit or needing to invest in a part what will last. The Revolution Series is designed for you!