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.
Size 5 is the official size for professional matches. Therefore, this ball is only available in this size. Do not use this soccer ball on concreted areas. Its unique rubber uses Puma Airlock Valve Technology (PAL) in order to facilitate proper airlock technology. This ball features Perimeter Balance Technology (PBT) which enables it to maintain impressive flight characteristics. https://www.youtube.com/watch?v=j2Xn84L3Kcs