Volley Balls

The ball is:

• spherical
• made of leather or other suitable material
• of a circumference of not more than 70 cm (28 ins) and not less than 68 cm (27 ins)
• not more than 450 g (16 oz) and not less than 410 g (14 oz) in weight at the start of the match
• of a pressure equal to 0.6 – 1.1 atmosphere (600 – 1,100 g/cm² ) at sea level (8.5 lbs/sq in – 15.6 lbs/sq in)