6.1 Tours including the old PS Tour, NCode Tour 90, and the current K Tour 90. I mean, to market the exclusivity of N or K90 used only by Federer, does Wilson stop other pro players from using it? Say someone wants to use K90, but Wilson says you can't use it, we'll sponsor you K95 + pro-shop modification instead. And these pros just accept this, because Wilson pays them better than other racket companies and they understand that with pro mod, the exact model doesn't matter much any more. And then we have in the tennis world: only Fed uses K90, because of Wilson's barrier of entry. A smart marketing by Wilson. And does this invalidate the argument that no other pros can use the K90 but Fed?