YAD Shimano Rear Derailleur RD-TZ31 6/7 Speed Hanger Mount for Mountain Bike This is hub bolt mount, NOT direct mount, please check the mount type of your original part before you buy it Material: High quality plastic and alloy 6/7 speed SIS index shift, fit for mountain bike/road bike For 6/7 grade freewheel, mainly used in aluminum alloy bike frame Shipped within 24 Hours, Quick delivery; Superb Customers Care; Warranty: 2 Years