Babolat Addixion 17 660' Reel Tennis String Reels : The Babolat Addixion 17 660' Reel tennis strings are perfect for players who want a blend of power, comfort, and durability. Formerly known as the Babolat Addiction 17, these multifilament strings have a central core with polyamide-fibers and a polyurethane matrix to combine power and comfort. PTFE fibers provide increased durability from the low coefficient of friction in the material. Power: 3/5 Durability: 3/5 Comfort: 4.5/5