RD-TZ31-A 7-speed rear derailleur for 6/7-speed mountain bikes, delivering smooth shifting across gears for confident riding on suspension and trail surfaces. - Installation flexibility: Direct mount or hanger mount design lets you install on frames with either configuration. - Sleek appearance: Black finish provides a clean, low-profile look that complements modern mountain bikes. - Built for mountain biking: Specifically designed to withstand off-road use, rough terrain and vibrations for reliable performance. - Convenience and compatibility: Model RD-TZ31A-Hanger includes the necessary hanger for installation, streamlining setup. Use scenarios - Upgrading a 6/7-speed mountain bike to achieve smoother gear changes on hills and technical sections during trail rides. - Replacing a worn derailleur after long cross-country rides to maintain consistent shifting on rough terrain. - Building or upgrading a versatile hardtail with mounting flexibility and an included hanger for easy, quick installation.