Bike Training Wheels for 12 14 16 18 20 inch Variable Speed and Single Speed Kids Bike. Extension Bolts are included to solve the problem of installing training wheels on bicycles with short rear axles. The training wheels are easy to install and remove, allowing parents to adjust the height as their child grows. The wheels are equipped with rubber tires that provide a smooth and comfortable ride. Constructed with a sturdy frame, these training wheels can withstand the weight and impact of outdoor use. The frame is designed to provide a stable and secure ride. Crafted with high-quality rubber materials, these bicycle training wheels offer slip-resistant and wear-resistant performance, ensuring a stable riding experience for children. These training wheels are popular with both boys and girls and make a great gift for kids. Color: Black. Material: Iron + Rubber. Package Contents: 2 x Screw, 2 x Side Wheel. Note: Only the items listed are included. Light reflection and different displays may cause the color in the image to vary slightly from the actual product. Measurement may vary by +/- 1-3 cm.