 Popular lawn tennis rackets vary primarily in length, weight, balance point, stiffness, beam thickness, string pattern, string density, and head size.They generally conform to unofficial standards that differ from past rackets.Currently, almost all adult rackets produced by companies such as Prince Sports, Yonex, Wilson, Babolat , Dunlop Sport, Head, Tecnifibre, and Völkl are made from a graphite composite.