Luxilon ALU Power is one of the most popular strings on the ATP Tour. An extra fine, superior durability string which combines impressive power with great control and feel. Its characteristics also include no noticeable tension loss, less plastic deformation than most polyester strings. CompositionCo ploymer Nylon, Florocarbon resin, aluminum fibersGauge16LLength40'Durability8.66Playability6.9TypeCo PolyesterTensionString 10% less tension than rec.