The Raskullz Training Wheelsz are heavy-duty training wheels designed for bikes with a wheel size of 12-20 inches. With a weight capacity of 85 lbs., these outdoor training wheels are made of steel material and come in a set of 2. The black color and high durability features make them suitable for beginners looking to learn how to cycle. Manufactured by Bell Sports in the United States, these training wheels provide stability and support for young cyclists, helping them develop their cycling skills in a safe environment.