Sturdy Material: Training wheels Compatible with children are made of high-quality ABS wheels and high-quality metal. The training wheels are durable, non-slip, and wear-resistant, providing stability, helping children ride bicycles, and allowing children to enjoy the fun of cycling. .Safe and Helpful: Your children's safety is our top priority. High-quality training wheels help beginners maintain balance and provide greater safety and stability until they learn to ride a bicycle. Without holding the saddle, you ensure your children's safety. .Universal Size: Our universal training wheels Compatible with children's bicycles fit 12 14 16 18 20 inch children's bicycles, meeting children's needs to learn to ride a bicycle as they grow up. Please check if these wheels are compatible with your bicycle. .Flash Design: Our training wheels Compatible with toddlers are non-slip and quiet. Especially with the flash function, children are more interested in cycling at night. Bicycle stabilizer wheels are a good helper Compatible with your child's first cycling lesson. Easy to Install: The 20-inch training wheel set includes two axle bolts, two nuts, two washers, limiting spacer, two vertical brackets, and two wheels. Use two wrenches Compatible with mounting the training wheel on the child's bicycle's rear wheel, and you can adjust the distance between the vertical bracket and the ground.