[Sturdy and durable materials] - The bicycle training wheels are made of high quality rubber with steel support arms, sturdy and durable, not easy to be damaged. Ideal for stability and safety, can help children quickly find their balance and prevent falls. [Strong Support Arms] - The support arms of the small support bike caster is made of high quality steel, not easy to rust and corrode, and is 3mm thick. It is more durable than conventional grab arms and is not easily damaged, is a practical child's bicycle assistant, and better guarantees children's safety when riding. [Adjustable design ] - There are 5 pants on the auxiliary wheel support arm, you can adjust the height according to the size of the wheel, suitable for 12-16 inch children's bikes, can meet your needs Please be sure that the rear wheel bearing of your bicycle can be equipped with auxiliary wheels before purchase. [Easy to assemble] - This kit includes 1 pair of black bicycle wheels with two support arms and screws corresponding parts as well as a multi-function bicycle key with which you can quickly and easily mount the small bicycle wheels on the bicycle, it is very convenient and fast. [Good children's bicycle helper] - This children's bicycle stabilizer is ideal for boys and girls who want to learn to ride a bicycle, designed for beginners' cycling practice. Ideal for learning on a bike with children's bike rear wheels to start gaining confidence on the bike and eliminating fears.