Product packaging: 2 x auxiliary wheel, 2 x shoulder bolts, 2 x screw caps, 2 x washers, 2 x lock nuts, 2 x handguard washers, 1 x wrench. 2. SUPER HIGH QUALITY: Our bicycle auxiliary wheels are made of high quality metal, plastic and rubber materials. 3. UNIQUE DESIGN: We are most concerned about the safety of our customers. The training bike has a small bracket, which is more stable and can help young students ride a bike until they feel the balance of the bike, so you don't have to worry about your kids' safety. 4. High-quality flash wheels: non-slip, wear-resistant, stable, stabilizer bars are 3.0mm thick. This offers beginners more security and stability. Black wheels are perfect for any colored bike. 5. UNIVERSAL AND ADJUSTABLE: The stabilizers will fit 12 or 14 or 16 or 18 or 20 inch single speed bikes with horizontal, rear-facing fork end, but are not suitable for those with semi-horizontal or vertical dropouts. Safety Your children is our top priority. Heavy-duty stabilizers help beginners keep their balance and add security and stability until they learn to ride a bike. Keep your kids safe without holding the saddle. Perfect bike accessory for those who are unfamiliar with cycling or afraid of falling. They have the function, to be non-slip and noiseless, so that your child can drive more safely and smoothly without worrying. The extra wheel can light up when the car is running. Fits most bikes. This bike training wheel gives children more courage when they are out and about and can be seen as an important part of their development. The stabilizers can be adjusted to suit the skill and level of the trainer. We care deeply about the safety of our customers. The training bike added a small bracket, which is more stable and helps young students ride bikes until they have balance on the bike, so you don't have to worry about your kids' safety.