We focused on children's safety so that the bearing doesn't break easily. COMPATIBLE WITH MOST KIDS BICYCLE: Training wheels for girl and boy are available for 12, 14, 16, 18, 20 inch bikes, But the HUFFY kids bike is . FLASH LIGHTS :Wheels light up when they spin above 1m/s smoothly, creating much fun and kids can ride in dark environment. DURABLE PU:The bicycle training wheels are made of high quality PU and plastic with extra thickness which is anti-slippery and wear resistant. It creates a condition for kids to ride without fears. For children's safety, we upgraded durability over other products. You can see the difference if you compare it directly with other products and photos. We have upgraded the wheel design and bearings. Let the kids enjoy riding their bikes with the LED light from the . Training wheels are essential for children to learn how to ride safely. memories about bicycles to your children. Colour: Black Material: metal +PU Package Contents: 2 x LED wheels 2 sets x installation accessories 2 x wheel mounting brackets Only the above package content, other products are not included. Note: Light and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.