EXO3 features The Energy Channel, a radical new frame design which creates elongated open channels located at the 12, 3 and 9 o’clock positions of the frame – which moves the mass to the outer most edges of the frame for exceptional stability. Complementing the Energy ChannelTM of EXO3 is a visible, engineering breakthrough called the Energy BridgeTM. Soft thermoplastic pieces are inserted into the Energy Channel to create an exo-skeletal bridge structure along the outside surface of the frame. The result is a string bed that is almost entirely suspended from the frame itself. EXO3 Black Unstrung Weight: 170-180 grams Balance: 1 point head heavy String: Premier Power 17 (Black) String Tension: 34 +/- 4 lbs Grip: Vision II Vision II Grip Sizes: SSR, SS, SM Power Level: 4000