great value Acera dual pull multi-fit front triple derailleur offering crisp performance on and off-road for 9-Speed drivetrains top swing design for positive shifting action dual pull design allows it to be used with top or bottom cable routing multi-fit design for 28.6, 31.8 and 34.9 mm frame tubes for bike designs with 66-69 degree chain stay to seat tube angle for use with 40 tooth outer chain rings compatible with 9-Speed drivetrains.