【Reliable Construction】: Made from quality, thick PVC material, ensuring spike replacement balls are sturdy and resistant to damage. The premium material offers good elasticity and abrasion resistance, making it suitable for long-term use. 【Quick and Convenient Inflation】: Equipped with a fast inflation pump, allowing for simple and quick inflation to save time. Maintains good air pressure after inflation, reducing the need for frequent adjustments for ease of use. 【Versatile Usage Across Various Settings】: Roundnet game replacement balls are ideal not only for indoor volleyball games but also great for outdoor activities and family entertainment. Its versatility allows you to enjoy sports anytime, anywhere. 【Materials】: Spike game balls are made from quality PVC material, ensuring reliability. Suitable for both children and adults. 【Compact Size with Complete Set】: Features a compact diameter design that is easy to handle. Comes as a complete set including balls and an air pump, ready for immediate play. Specification: Material: PVC Package Includes: Spike game balls and pump Note: Please allow slight errors of 1-2 cm or 0.39-0.79 inch due to manual measurement.