Tecnifibre evolves their TFight line again with the TFight ISO 305 Tennis Racquet . Endorsed on tour by US Open champion , The 305 features Tecnifbre`s RS beam design, which pairs the control and stability of a square beam shape with the power of a more rounded one. Tecnifibre enhanced the TFight 305 with Isoflex technology . The stringbed is designed to feature a softer flex and feel throughout the sweet spot, where the strings are longest, and a more powerful response from the racquet on off center hits, where the strings are shorter. The racquet features a 10.8 ounce unstrung weight with a controlled yet explosive 18x19 string pattern. The ISO 305 is filled with foam to provide additional feel and dampening. The racquet is a good choice for high performance players who can generate high swing speeds. The string pattern offers impressive control, and the Isoflex technology helps with pace and stability on off-center hits.