This transmission is perfect for mountain bicycle or bike speed shift. Beautiful shape, this design is more space-saving. Good grip, better and comfortable handling, non-slip. High-quality rubber material, high durability. Red + black color design, give your bicycle an outstanding look. Designed for ease of use, this combination pair replaces separate brake lever and gear shift systems with shift cables. The slick cables made of durable metal allow for better braking power and smooth operation. If you have any questions, please email us for a prompt response within 24 hours.