Born from the minds of your favorite tennis fanatics, the Solinco Hyper-G Round 17 + Mach-G 17 Hybrid turns your racquet into a powerhouse! This co-poly string merges Brain Dead's chosen strings -- Hyper-G Round and Mach-10--to deliver a high-powered combination. Engineered by ...Born from the minds of your favorite tennis fanatics, the Solinco Hyper-G Round 17 + Mach-G 17 Hybrid turns your racquet into a powerhouse! This co-poly string merges Brain Dead's chosen strings -- Hyper-G Round and Mach-10--to deliver a high-powered combination. Engineered by Solinco, designed by Brain Dead, the Hyper-G Round 17 + Mach-G 17 Hybrid cranks power and feel to another level! Use Hyper-G round in the mains for a deeper, more penetrating ball Use Hyper-G round in the crosses for a heavier, spin-friendly ball.