<P> Elements of the football that today are tested are the deformation of the football when it is kicked or when the ball hits a surface . Two styles of footballs have been tested by the Sports Technology Research Group of Wolfson School of Mechanical and Manufacturing Engineering in Loughborough University; these two models are called the Basic FE model and the Developed FE model of the football . The basic model considered the ball as being a spherical shell with isotropic material properties . The developed model also utilised isotropic material properties but included an additional stiffer stitching seam region . </P> <P> Companies such as Umbro, Mitre, Adidas, Nike, Select and Puma are releasing footballs made out of new materials which are intended to provide more accurate flight and more power to be transferred to the football . </P> <P> Today's footballs are more complex than past footballs . Most modern footballs consist of twelve regular pentagonal and twenty regular hexagonal panels positioned in a truncated icosahedron spherical geometry . Some premium - grade 32 - panel balls use non-regular polygons to give a closer approximation to sphericality . The inside of the football is made up of a latex bladder which enables the football to be pressurised . The ball's panel pairs are stitched along the edge; this procedure can either be performed manually or with a machine . The size of a football is roughly 22 cm (8.65 inches) in diameter for a regulation size 5 ball . Rules state that a size 5 ball must be 68 to 70 cm in circumference . Averaging that to 69 cm and then dividing by π gives about 22 cm for a diameter . </P> <P> The ball's weight must be in the range of 410 to 450 grams (14 to 16 oz) and inflated to a pressure of between 0.6 and 1.1 standard atmospheres (8.8 and 16.2 psi) at sea level . </P>

What are the details of ball used in football