One of the best-kept string secrets of the pros is now available to the public.

Solinco has unwrapped its co-polyester tennis string, Confidential, for retail sale.

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 Initially developed specifically for top touring pros, Confidential caught on as a popular choice on the pro circuit. Confidential features Solinco's signature blend of spin, power and control with added playability.

Solinco Confidential is available in 16, 16L, 17 & 18 gauges in both 12 meter individual sets and 200 meter reels.

Numerous top 100 ATP and WTA professionals have chosen Confidential as their string of choice, and has already been used to win a singles Grand Slam championship.

“We are very excited to finally launch Confidential, the newest string in our product line,” said KT Kim, Director of Solinco. “The evolution of this string is quite unique for us, as we had not originally planned to add this co-polyester string to our product line.

"However, as more players heard and tested the string, a strong interest and demand for the product grew and we ultimately realized that we needed to make this available for everyone to try."