bike Training Wheels for 12 14 16 18 20 inch Variable Speed and Single Speed Kids Bike,Extension Bolts are used to solve the problem of not being to install 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. Our training wheels are constructed with a sturdy frame that can withstand the weight and impact of outdoor use. The frame is designed to provide a stable and secure ride. Crafted with top-quality rubber materials, these bicycle training wheels boast slip-resistant, wear-resistant , ensuring a stable riding experience for kids. This training wheels are very popular with boys and girls, that is one of the good gifts that will continue to bring joy to kids. If you want to express your love for them ! Color: Black Material: iron+rubber Package Contents: 2 x screw 2 x Side wheel Only the above package content, other products are not included. Note: Light reflection 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.