A. Stabilizers For kids Bike: Child safety is important. Our Bike Stabilisers weighs 1.1KG. Heavy-duty training wheels help children maintain balance and provide safety and stability. B. Rugged and Durable: the upgraded version of thick 3MM high-strength carbon steel material, stable riding without deformation. The wheels are made of environmentally friendly PVC material, non-slip, wear-resistant, durable and low noise. C. Easy to Install: Use a wrench to install the training wheel on the rear wheel of the bicycle to adjust the distance between the vertical support and the ground. D. Bike Stabilisers 18 20 22 24 Inch: Bike Stabilisers are suitable for 18 20 22 24 inch bicycles, meeting the needs of children learning to ride in different periods and giving them a safe support. Enjoy Fun of cycling. E. Compatibility: Bike Stabilisers are suitable for children's bicycles and variable-speed bicycles. Install our special extension screws on the shifting side. After installation, please make the main wheel perpendicular to the ground, and confirm that the auxiliary wheels on both sides have a height of about 0.6-1cm from the ground. (Installation tools are provided by yourself)