Portable Airless Technology: These Balance Bike Replacement Wheels feature innovative airless technology, eliminating the need for inflation and the worries of leaks or blowouts Double Materials Construction: Crafted with a sturdy PP hub and flexible PE tires, these Training Wheels are designed to withstand rough terrains without breaking or wearing out easily Product Dimensions: This pair of wheels has a diameter of 27 cm/10.63 inch, with a distance between two bearings of 6 cm/2.36 inch, ensuring a secure fit and easy installation Shock Absorption and Noise Reduction: The Training Bicycle Tyre structure effectively absorbs road vibrations for smoother rides while minimizing noise levels, making it ideal for quiet riding Enhanced Safety Features: With a sturdy wheel design and anti-slip patterns, these training bicycle wheels offer great grip to help prevent slipping or tipping over Specification: Material: PP, PE Size Chart: Diameter: 27 cm/10.63 inch Distance Between Two Bearings: 6 cm/2.36 inch Package Includes: 1 Pair Balance Bike Replacement Wheels Note: Please allow slight measurement errors of 1-2 cm/0.39-0.79 inch due to manual measurement