In order to raise money for charity, Wilson has released limited edition versions of their (K) Factor tennis rackets which are inlaid with gold leaf designs. They are well-known because they were used by multiple Grand Slam champions Venus and Serena Williams at this year’s Wimbledon. Only 650 of each model will be available at a recommended retail price of $500; ten percent of the proceeds go to The Breast Cancer Research Foundation (BCRF). Serena and Venus signed an additional ten rackets of each model which are to be auctioned for the charity. Note: Venus used the white frame, Serena the black one.