Yonex V-Mass 350. The Yonex V-Mass 350 features a 290cc Titanium head which helps generate explosive power at impact, providing distance without the loss of accuracy. Engineered into the sole are two strategically placed Tungsten Inserts. These Tungsten Inserts square the clubhead at impact, deepen the centre of gravity which makes for an enlarged sweet spot and helps get the ball airborne more easily.