Balance wheels M-Wave Training Wheels 12″ – 20″are universal 12-20″ wheels for children’s wheels. These balance wheels are designed for beginners who need help with balancing.Technical description:one pair of balancing wheelsdesigned for children’s bicycles with a wheel size of 12-20 “- adjustable according to the size of the wheeleasy installationanti-roll protectionwheel diameter: 5 “