Stiff Flex. The TSR1 driver is built for ultralightweight speed and distance and provides players the launch characteristics and speed to deliver effortless added yards to every drive.As a maximum performance 460cc driver, TSR1 is roughly 40 grams lighter than TSR2, with weight savings coming from a lighter headweight, 40gram shaft and lightweight grip. The elimination of excess weight, combined with improved aerodynamics and a similar boat tail shape to TSR2, helps golfers swing TSR1 faster through the air. MultiPlateau Variable Face Thickness technology found in other TSR driver models assists in speed retention from offcenter hits, while a deep CG almost perfectly centered to the face promotes higher launch and exceptional ball speed.