Wilson Champion's Choice Duo combines Luxilon Big Banger ALU Power Rough with Wilson Natural Gut 16, as used by Roger Federer. This produces perfectly matched performance-the durability of Luxilon ALU Power Rough with the unmatched performance and feel of Wilson Natural Gut. Superior balance of ultimate playability Wilson Natural Gut playability and Luxilon Big Banger ALU Power Rough monofilament durability demanded by all court players.