Purpose and benefit Secures the crankset and crank on the chainwheel to provide a stable, reliable connection that prevents loosening during rides Simplifies installation and removal so routine maintenance and component swaps are faster and easier Corrosionresistant construction extends service life and reduces the need for frequent replacement Compatibility Designed for Shimano and components built to the same specifications Fits common Shimano model families such as M590, M596, SLX, XT, and XTR Key specifications Cover size: approximately 28 mm x 15 mm Thread diameter: M20 Height: 11 mm Please allow 1–2 mm variation due to manual measurement Installation and use Install or remove using a 3/8' (10 mm) Allen wrench Straightforward fit and alignment for quick workshop or field servicing Material and performance Made from aluminum alloy for a balance of strength and low weight Antirust and corrosionresistant finish for reliable performance in wet or dirty conditions Durable construction resists wear from repeated installation and removal Practical use scenarios Replacing a worn or damaged crank bolt during a routine drivetrain service Upgrading or assembling a Shimanocompatible crankset on a mountain or trail bike Quick roadside to resecure a crank after a bolt has loosened midride Why choose this part Accurate fit for Shimanospec cranksets ensures correct function and safety Durable aluminum construction reduces corrosion and maintenance needs Easy, toolfriendly installation saves time in both and field environments