Tourna Quasi Gut Premium Multifilament Tennis String for Tennis Elbow Premium multifilament tennis String Constructed of Thousands of Microfibers for a "gut-like" feel Each fiber is coated with a PU resin to to increase durability and offer weather shielding Top 10 rating in touch, feel, playability, comfort and power Great for tennis Elbow sufferers.From the makers of Tourna grip, the #1 tennis grip in the world