Great value 2-piece design 9-speed chainset offering slick hyperdrive shifting performance for off-road enthusiasts. The Mega-9 chainset provides smooth hyperdrive shifting performance. Its 2-piece design features an external bottom bracket system, resulting in a lightweight, rigid, strong, and durable build. The chainset includes a lightweight and rigid steel bottom bracket axle. This model has a 51.8 mm chain line (boost) and does not come with a chainguard.