The All Mountain Style Crank Defenders are protect your cranks against nicks and dings while out riding. Features: An elegant solution to protect your cranks and add style at the same time Fits most carbon and some aluminum cranks; See compatibility list at: https://www.allmountainstyle.com/pages/ams-crank-defender-compatibility-list Tight fit to keep debris from becoming an issue Includes 4 pieces to extend protection up crank arm