Welcome to our store!<br> 1. Secondary Wheel Material: The main body of the secondary wheel is made of PU material, which has high wear resistance and won't wear out too much after long rides.<br> 2. Product Principle: The luminous wheel's principle is that the built-in micro-generator can rotate to generate electricity and light up the lamp (no battery required).<br> 3. Anti-Slip: Our kids' bike training wheels are designed to be anti-slip for a safer and easier ride. Your child will have a smoother ride, and you can have peace of mind as they learn to cycle.<br> 4. Support Process: The support uses a multi-layer baking paint process, with a smooth surface and no burrs, and is not easy to scratch hands during installation.<br> 5. Easy to Install: Our bike training wheels can be installed on your child's bike quickly and easily. Just install, and your child is ready to ride!<br> Item Type: Kids Bike Training Wheels<br> Product Material: PU, Carbon Steel<br> Product Color: Black<br> Weight: Approx. 690g / 24.3oz<br> Wheel Diameter: Approx. 11cm / 4.3in<br> Package Contents:<br> 2 x Axle Bolt<br> 2 x Training Wheel<br> 2 x Vertical Support<br> 2 x Washer<br> 2 x Lock Nut<br> 2 x Limiting Gasket<br> 1 x Wrench<br> Satisfaction Guaranteed: Customers are our top priority. If you find any issues with the product, please contact the seller immediately. We strive to provide satisfactory after-sales customer service.