Magura disc brake adapters let you mount your Magura disc brake to your fork or frame. Features: Choose from post mount or IS mount and a variety of rotor configurations Includes hardware to mount the adaptor to the forks/frame Specifications: Frame Mount Options: IS Mount (International Standard, 51mm), Post Mount (74mm) Caliper Mount: Post Mount (74mm) Color: Black Weight: 30g (QM12) Models: QM12: For a 180mm rotor with 6" IS front fork or 160mm rotor with IS rear frame mount QM40: For a 180mm rotor with 6" front post mounts or a 160mm rotor with 5" rear post mounts QM41: For a 180mm rotor with 6" rear IS mounts QM42: For a 203mm rotor with 6" front post mounts QM43: For a 160mm rotor with 6" IS mount front fork. Also works for a 203mm rotor with pre-2014 Fox 40 forks (8" IS Mount).