Great for the mountain bike lovers.Features:Iron material， durable and useful.You can ride freely with the product.Suitable for most of mountain bikes.Specifications:Material: IronColor: SilverCog: 13Item Weight: 311g / 10.99ozPackage Size: 25 * 20 * 5cm / 9.84 * 7.87 * 1.97inPackage Weight: 321g / 11.31ozPackage List:1 * 7 Speed Rear Derailleur