Apacs Blend 8000 Badminton Racket (4u) Isomectric head frame - Equalizes the length of main and cross strings in the stringbed, enlarging the sweet-spot for more consistent accuracy even on off-center hits. Blend Technology Frame - This technology creates the blend between the speed and power of the frame that enables the player to enjoy the best of both world. Making your shots agile, fast and powerful. Reinforced Structure Frame - The new material is adopted in the frame in order to make the frame Ultra high Strength & Stiffness. As a result it can handle string tension of up to 38lbs. Graphite T-Throat - Strengthen frame and shaft stability, enhanced attacking power, increase shuttlecock velocity and improved accuracy of shuttlecock direction. Taper Shaft - Diameter 7.5mm on racket front cap and thin towards the top of racket at 7.0mm increase the flex point on racket frame to generate greater power and accurate shot.