Federer's 2004-2006 Racquet of Choice.

The nSix-One Tour 90 retains much of the same design as the Pro Staff Tour 90 that it replaces. The same 17mm straight box-beam design, headsize and 9 points head light balance are retained. Gone is the predominantly black look and textured paint around the upper hoop. Instead, the nSix-One Tour 90 features the bright red and white used throughout the nCode line. More importantly, it is under the paint where the most significant modification occurs. The nSix-One Tour 90's main technological feature is Wilson's nCode construction process.

The nCode construction process adds material to the frame at the nano level. According to Wilson, in an nCoded racquet, nano-sized silicone crystals permeate the voids between the carbon fibers. Wilson claims that their exclusive nano technology creates racquets that are two times stronger, two times more stable and up to 22% more powerful than ordinary racquets.