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who has won the most men's singles tennis titles
Roger Federer has won the most Grand Slam titles, most recently the Australian Open in 2018, with a total of 20.
what was Roger Federer's playing style
An elite athlete, Roger Federer is an all-court, all-around player known for his speed, fluid style of play, and exceptional shot making.

Question: what is the player's equipment
Self-contained rewrite: what is Roger Federer's equipment