Option: 1, 34.9mm 2, 31.8mm(34.9mm with adapter) —————————————————————————— Model: FD-M2020 Level: Altus Speed: 2×9 Speed Compatible chain: HG 9-speed Mount: Clamp-on Clamp Band size: 31.8mm/34.9mm (31.8mm=34.9mm with adapter) Action: Top swing Cable route type: Dual-Pull(Top and down pull) Top gear teeth: 36T Total capacity: 14T Designed for 2x9 speed drivetrains Precise and reliable shifting, consistent off-road front shifting
