The yonex vcore si 98 g tennis racket is slightly heavier than the lg version in this range but it retains the same great stability and measured power great for intermediate and advanced players the black micro core technology in the head delivers improved stability and reduces vibrations whilst the isometric technology increases the size of the heads sweet spot to provide more power and control the head light nature of the racquet keeps it manoeuvrable with good feel and yonexs latest