Product parameters: Color: Black Diameter: 11 cm Dimensions: 17.5 x 11 x 9 cm Package Contents: Wheel * 2 Bracket * 2 Screw Nut * 2 Fixed Buckle * 2 Product Description: Designed for street exercise for beginner cyclists, which will help learners until they develop a sense of bicycle balance Improve your child's safety and confidence. High quality ABS wheels and high quality steel bracket arms. Our training wheel bracket arms are 3.0mm thick. For beginners, this means more safety and stability The training wheels are suitable for most 12-20 inch single speed bikes with a horizontal rear-facing tie rod end The training wheels are made of high-quality rubber and provide the necessary safety and stability . With really big wheels any type of bike looks amazing, stylish and beautiful. These wheels are individually adjustable and easy to install. If you have any questions about this item, please feel free to contact us.