Wilson Synthetic Gut 16 Reel Tennis StringWilson Synthetic Gut Reel 16 Tennis String 1 Set Power & Comfort Synthetic Gut Power utilizes a solid core nylon string for crisp feel and control. High energy wraps increase responsiveness for more power and improved feel on contact. No matter your playing style, this string is easy on the arm and can help you get to the next level. Classic synthetic gut construction features solid core. Bi directional Nomex X Bands provide responsive energy return.