The Forten Thin Blend contains: Forten New Age 18 tennis string and Forten Sweet 17 tennis string. Aramid/Polyamid Hybrid. Forten Thin Blend tennis string is a powerful and durable combination that doesn’t sacrifice playability or spin control. This string truly represents the dawning of a new age in racquet sports. Forten New Age: (Mains) This Kevlar string provides incredible durability in a thin gauge string to also provide great spin potential and playability. Forten Sweet 17: (Crosses) “Sweet” in the sweetspot, that is! Forten uses a specially formulated bonding agent in the development of this 17 gauge synthetic gut. Sweet efficiently returns energy to the ball during serve and volley play for livelier response without tension loss. Its tensile strength allows it to take the pounding of a baseline rally. More about FORTEN Hybrid Tennis Strings: A hybrid consists of a string bed with two different strings for the mains and crosses. The mains run parallel to the racquet handle and the crosses run perpendicular to the racquet handle in the racquet frame. The main strings are the primary determinant of playability during competition and are the most likely to break (due to movement) during competition. In a hybrid configuration, when a durable string such as Aramid string or polyester string is used for the mains a more elastic string is used for th e cross strings, the result is durable main strings backed by softer, more responsive cross strings. When durable main strings are used, the cross strings can be very thin gauge string which opens up the overall string pattern in the racquet and introduces more top spin into the player’s game style.