(Made In ) Mini vollyball- 6.3cm. Ball This mini ball constructed of soft foam making it safe for use inside and as an indoor mini hoop ball. Soft, coated mini foam ball is quieter when bounced and shot making it the perfect (and less noisy!) option for kids vollyball inside the house or office vollyball. High-quality foam ball in mini 2.5" size is great for younger kids and adults.