Nike Free Flyknit Mercurial Trainers PITCH-INSPIRED STYLE. The Nike Free Flyknit Mercurial Men's Shoe reimagines the iconic Mercurial Superfly boot for everyday wear. Its Flyknit constructed upper boasts a comfortable, sock-like fit and the Nike Free 5.0 outsole gives you an incredibly lightweight feel. Details: • Flyknit constructed upper conforms to your foot for lightweight support • High-cut collar for a secure, comfortable fit • Nike Free 5.0 outsole gives you natural-motion flexibility • Sticky rubber outsole offers durable traction