Muscle Power 5--Model 2012
New for 2012!!!  New Musclepower series replaces the old Isometric Line.  MUSCLE POWER 5 FEATURES:MUSCLE POWER: Muscle Power seats the string on rounded archways that eliminate stress-load and fatigue through contact friction. The construction creates total unity of the string and frame through closer-and-tighter contact.ISOMETRIC: The Isometric Square Head Shape equalizes the length of main and cross strings in the stringbed, enlarging the sweetspot for more consistent accuracy even on off-center hits.BUILT IN T-JOINT: Moulded deep into the layers of graphite where the frame connects with the shaft, the Yonex built-in T-Joint creates a durable and high-strength one-piece frame that is torque-free.