Usage Tips: Universal Compatibility: Designed to fit most children's glider bikes, training bicycles, and balance bikes with a 12-inch wheel size, ensuring a versatile replacement option Reinforced Nylon Hubs: These hubs are sturdy and long-lasting, ensuring they won't easily break even with extended use Quiet Design: Engineered for silent operation, these wheels significantly reduce rolling noise, providing a smoother and more comfortable riding experience for your child Easy Installation: Replace the wheels in just a few simple steps without the need for professional tools, making it convenient for parents to handle on their own Complete Set: Comes as a pair of balance bike replacement wheels, great for refreshing or upgrading your child's ride with ease Specification: Material: Metal and Plastic Size Chart: Diameter: 30 cm / 11.81 inches Width: 4.5 cm / 1.77 inches Package Includes: 1 Pair Balance Bike Replacement Wheels Note: Please allow slight errors of 1–2 cm (0.39–0.79 inches) due to manual measurement