The Shimano MT520 Crankset's two-piece alloy design is built for trail and enduro riding. DYNAMIC CHAIN ENGAGEMENT+ optimizes the narrow-wide tooth profile for consistent chain retention, and a four-arm steel chainring adds strength where the drivetrain takes the most stress. What Our Gearhead(R) Experts Are Saying:"This crank's tech keeps the chain seated through rough terrain without needing a separate chain guide. The four-arm steel chainring holds its shape through a full season of hard riding."